Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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lee
 
Posts: n/a
Default combining 2 power supplies

Hi,

Over the years, I've kept a few ATX power supply from old computers. Now,
I'm thinking about upgrading my computer and add more hard disks. The
problem is the current power supply might not be able to support so many
hard disks running at the same time. Instead of buying a new, more powerful
power supply, I am planning to use one old piece (350w) to serve the
motherboard, CD, and 3 hard disks, then another power supply (350w too) to
serve 3 to 4 more hard disks. All components are connected to the same
motherboard. I need to know how I could turn on both power supply with a
single press of the power button on the case.

In other words, only one power supply can plug to the motherboard, how can I
jam the wires together so that the second power supply receive the power-on
signal when I press the button? I was thinking about the Power-On (Green),
Power-Good (Gray) and 5 VSB (Purple) wires. the second power supply would
only support the hard disks and nothing else, but I need them to be powered
up at the same time other hardware are up (and down when it's shut down).

Thanks.


  #2   Report Post  
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crazy frog
 
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Default combining 2 power supplies

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.

"lee" wrote in message ...
Hi,

Over the years, I've kept a few ATX power supply from old computers. Now,
I'm thinking about upgrading my computer and add more hard disks. The
problem is the current power supply might not be able to support so many
hard disks running at the same time. Instead of buying a new, more

powerful
power supply, I am planning to use one old piece (350w) to serve the
motherboard, CD, and 3 hard disks, then another power supply (350w too) to
serve 3 to 4 more hard disks. All components are connected to the same
motherboard. I need to know how I could turn on both power supply with a
single press of the power button on the case.

In other words, only one power supply can plug to the motherboard, how can

I
jam the wires together so that the second power supply receive the

power-on
signal when I press the button? I was thinking about the Power-On

(Green),
Power-Good (Gray) and 5 VSB (Purple) wires. the second power supply would
only support the hard disks and nothing else, but I need them to be

powered
up at the same time other hardware are up (and down when it's shut down).

Thanks.




  #3   Report Post  
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Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.


100 ohms may be too high. 5 ohms probably better. But an automotive
taillight (incandescent) or dead harddrive also should work.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
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  #4   Report Post  
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Ian Stirling
 
Posts: n/a
Default combining 2 power supplies

lee wrote:
Hi,

Over the years, I've kept a few ATX power supply from old computers. Now,
I'm thinking about upgrading my computer and add more hard disks. The
problem is the current power supply might not be able to support so many
hard disks running at the same time. Instead of buying a new, more powerful
power supply, I am planning to use one old piece (350w) to serve the
motherboard, CD, and 3 hard disks, then another power supply (350w too) to


Do the numbers.
Only 8 should not be a problem, if it's a real 350W.

15W * 8 = only 120W.
Add another 100W for the motherboard, and you're pretty much fine.

Also.
You'll want to do the numbers on life cycle cost.
Yes, you may have 3 80G drives spare, that you can stick into a system.
If you're going to be leaving them on (which increases drive life), then
in some places, you'll pay for a new 240G drive in a couple of years.
  #5   Report Post  
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lee
 
Posts: n/a
Default combining 2 power supplies

Thanks and I did my numbers:

I'm thinking a P4 9xx CPU and it draws around 100w alone, new display cards
(ATI x series) also draws a lot of power. More than 1 web site said hard
disks draws 25w so I use that in my calculation to be on the safe side.
Plus RAM, DVD-RW, fans, and USB devices that might connect to the machine
every now and then. Each of those costs little but they add up. 350w might
not be sufficient all the time. In addition, I don't trust the PSU will
produce 350w as claimed by the manufacturer.

In the meanwhile, thank you for everyone's help in this.

Best regards.

"Ian Stirling" wrote in message
...
lee wrote:
Hi,

Over the years, I've kept a few ATX power supply from old computers.
Now,
I'm thinking about upgrading my computer and add more hard disks. The
problem is the current power supply might not be able to support so many
hard disks running at the same time. Instead of buying a new, more
powerful
power supply, I am planning to use one old piece (350w) to serve the
motherboard, CD, and 3 hard disks, then another power supply (350w too)
to


Do the numbers.
Only 8 should not be a problem, if it's a real 350W.

15W * 8 = only 120W.
Add another 100W for the motherboard, and you're pretty much fine.

Also.
You'll want to do the numbers on life cycle cost.
Yes, you may have 3 80G drives spare, that you can stick into a system.
If you're going to be leaving them on (which increases drive life), then
in some places, you'll pay for a new 240G drive in a couple of years.





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James Sweet
 
Posts: n/a
Default combining 2 power supplies

lee wrote:
Hi,

Over the years, I've kept a few ATX power supply from old computers. Now,
I'm thinking about upgrading my computer and add more hard disks. The
problem is the current power supply might not be able to support so many
hard disks running at the same time. Instead of buying a new, more powerful
power supply, I am planning to use one old piece (350w) to serve the
motherboard, CD, and 3 hard disks, then another power supply (350w too) to
serve 3 to 4 more hard disks. All components are connected to the same
motherboard. I need to know how I could turn on both power supply with a
single press of the power button on the case.

In other words, only one power supply can plug to the motherboard, how can I
jam the wires together so that the second power supply receive the power-on
signal when I press the button? I was thinking about the Power-On (Green),
Power-Good (Gray) and 5 VSB (Purple) wires. the second power supply would
only support the hard disks and nothing else, but I need them to be powered
up at the same time other hardware are up (and down when it's shut down).

Thanks.




There's a lot of wattage inflation these days, following the stereo
equipment makers in the 80s. The fact of the matter is that if you have
a *quality* 300 or 350W power supply, it should run just about anything
you can fit in the computer. I've measured a number of computers with a
power analyzer and I have yet to see one which draws more than 250W from
the wall under full load, most typical single CPU computers are down
around 160-180W even with multiple hard drives.
  #7   Report Post  
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Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

James Sweet writes:

There's a lot of wattage inflation these days, following the stereo
equipment makers in the 80s. The fact of the matter is that if you
have a *quality* 300 or 350W power supply, it should run just about
anything you can fit in the computer. I've measured a number of
computers with a power analyzer and I have yet to see one which draws
more than 250W from the wall under full load, most typical single CPU
computers are down around 160-180W even with multiple hard drives.


Don't fight it. People think that adding power supplies multiples the
speed of the PC by the number of power supplies added. No way to talk
them out of it.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
  #8   Report Post  
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crazy frog
 
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Default combining 2 power supplies

im useing a supply with no mobo
and 100ohm works fine.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.


100 ohms may be too high. 5 ohms probably better. But an automotive
taillight (incandescent) or dead harddrive also should work.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.



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crazy frog
 
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Default combining 2 power supplies

got the info from silicon chip.

"crazy frog" wrote in message
u...
im useing a supply with no mobo
and 100ohm works fine.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.


100 ohms may be too high. 5 ohms probably better. But an automotive
taillight (incandescent) or dead harddrive also should work.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header

above
is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.





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crazy frog
 
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Default combining 2 power supplies

no not all, look at silicon chips artical

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

im useing a supply with no mobo and 100ohm works fine.


And so you think this applies equally well to ALL power supplies?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.

100 ohms may be too high. 5 ohms probably better. But an automotive
taillight (incandescent) or dead harddrive also should work.





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crazy frog
 
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Default combining 2 power supplies

how do you think my power supply is working.

"crazy frog" wrote in message
...
no not all, look at silicon chips artical

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

im useing a supply with no mobo and 100ohm works fine.


And so you think this applies equally well to ALL power supplies?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header

above
is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.

100 ohms may be too high. 5 ohms probably better. But an

automotive
taillight (incandescent) or dead harddrive also should work.





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Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

"crazy frog" writes:

no not all, look at silicon chips artical


Perhaps a link?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

im useing a supply with no mobo and 100ohm works fine.


And so you think this applies equally well to ALL power supplies?


"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.

100 ohms may be too high. 5 ohms probably better. But an automotive
taillight (incandescent) or dead harddrive also should work.

  #13   Report Post  
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crazy frog
 
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Default combining 2 power supplies

www.siliconchip.com.au

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

no not all, look at silicon chips artical


Perhaps a link?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

im useing a supply with no mobo and 100ohm works fine.

And so you think this applies equally well to ALL power supplies?


"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.

100 ohms may be too high. 5 ohms probably better. But an

automotive
taillight (incandescent) or dead harddrive also should work.



  #14   Report Post  
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crazy frog
 
Posts: n/a
Default combining 2 power supplies

cant fined the old article on pc power
supplies.
thay hav a new one on useing them as a 13v
high power unit without a pc connected.

"crazy frog" wrote in message
u...
www.siliconchip.com.au

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

no not all, look at silicon chips artical


Perhaps a link?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header

above
is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

im useing a supply with no mobo and 100ohm works fine.

And so you think this applies equally well to ALL power supplies?


"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.

100 ohms may be too high. 5 ohms probably better. But an

automotive
taillight (incandescent) or dead harddrive also should work.





  #15   Report Post  
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Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

"crazy frog" writes:

www.siliconchip.com.au


What article?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.


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Dave (from the UK)
 
Posts: n/a
Default combining 2 power supplies

crazy frog wrote:
green wire to black ground starts them up, but put
a load on them first like youre drives.
only the motherboard needs power good.
if running with no load, use a 5watt 100ohm resistor
accross the 5v+ to black ground for a dummy load.


Lets do a bit of maths.

5 V across 100 Ohms is 5^2 / 100 = 25 / 100 = 0.25 W. So you would only need 1/4
W restor, not a 5 W one.

However, like someone else, i think that would be totally inadequate as a
minimum load.




"lee" wrote in message ...

Hi,

Over the years, I've kept a few ATX power supply from old computers. Now,
I'm thinking about upgrading my computer and add more hard disks. The
problem is the current power supply might not be able to support so many
hard disks running at the same time. Instead of buying a new, more


powerful

power supply, I am planning to use one old piece (350w) to serve the
motherboard, CD, and 3 hard disks, then another power supply (350w too) to
serve 3 to 4 more hard disks. All components are connected to the same
motherboard. I need to know how I could turn on both power supply with a
single press of the power button on the case.

In other words, only one power supply can plug to the motherboard, how can


I

jam the wires together so that the second power supply receive the


power-on

signal when I press the button? I was thinking about the Power-On


(Green),

Power-Good (Gray) and 5 VSB (Purple) wires. the second power supply would
only support the hard disks and nothing else, but I need them to be


powered

up at the same time other hardware are up (and down when it's shut down).

Thanks.







--
Dave K MCSE.

MCSE = Minefield Consultant and Solitaire Expert.

Please note my email address changes periodically to avoid spam.
It is always of the form: month-year@domain. Hitting reply will work
for a couple of months only. Later set it manually.
  #17   Report Post  
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Dave (from the UK)
 
Posts: n/a
Default combining 2 power supplies

James Sweet wrote:

There's a lot of wattage inflation these days,


True.

following the stereo
equipment makers in the 80s. The fact of the matter is that if you have
a *quality* 300 or 350W power supply, it should run just about anything
you can fit in the computer. I've measured a number of computers with a
power analyzer and I have yet to see one which draws more than 250W from
the wall under full load, most typical single CPU computers are down
around 160-180W even with multiple hard drives.


But I don't belive that 250 W drawn from the mains is a likely maximum now.

I was doing some calculuations the other day based on a pair of Opterons.
According to AMD, they are about 100 W each. A very mediocre graphics card is
probably 30 W. Disks take more when they spin up.

350 W is probably adequate for most things I would agree. My main PC (I don't
use PCs much) has a 235 W power supply in it, but a pair of 450 MHz Pentiums and
a 10,000 rpm SCSI disk. That seems to be OK

A more elegant solution if there are multiple disks might be to build a timer
that delays the starts on them, as the power when running is probalby only half
that when starting.

Personally, I think I'd just rather buy a bigger psu - they are not that
expensive now.


--
Dave K MCSE.

MCSE = Minefield Consultant and Solitaire Expert.

Please note my email address changes periodically to avoid spam.
It is always of the form: month-year@domain. Hitting reply will work
for a couple of months only. Later set it manually.
  #18   Report Post  
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Franc Zabkar
 
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Default combining 2 power supplies

On Sun, 26 Mar 2006 19:48:42 GMT, James Sweet
put finger to keyboard and composed:

The fact of the matter is that if you have
a *quality* 300 or 350W power supply, it should run just about anything
you can fit in the computer. I've measured a number of computers with a
power analyzer and I have yet to see one which draws more than 250W from
the wall under full load, most typical single CPU computers are down
around 160-180W even with multiple hard drives.


I've measured ~175W for my single HDD, Athlon XP 2500+ system.

These are my idling and standby power consumption data:
http://groups.google.com/group/alt.c...e=source&hl=en

- Franc Zabkar
--
Please remove one 'i' from my address when replying by email.
  #19   Report Post  
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James Sweet
 
Posts: n/a
Default combining 2 power supplies

Dave (from the UK) wrote:
James Sweet wrote:

There's a lot of wattage inflation these days,



True.

following the stereo equipment makers in the 80s. The fact of the
matter is that if you have a *quality* 300 or 350W power supply, it
should run just about anything you can fit in the computer. I've
measured a number of computers with a power analyzer and I have yet to
see one which draws more than 250W from the wall under full load, most
typical single CPU computers are down around 160-180W even with
multiple hard drives.



But I don't belive that 250 W drawn from the mains is a likely maximum now.

I was doing some calculuations the other day based on a pair of
Opterons. According to AMD, they are about 100 W each. A very mediocre
graphics card is probably 30 W. Disks take more when they spin up.

350 W is probably adequate for most things I would agree. My main PC (I
don't use PCs much) has a 235 W power supply in it, but a pair of 450
MHz Pentiums and a 10,000 rpm SCSI disk. That seems to be OK

A more elegant solution if there are multiple disks might be to build a
timer that delays the starts on them, as the power when running is
probalby only half that when starting.

Personally, I think I'd just rather buy a bigger psu - they are not that
expensive now.




How many people have a pair of Opterons though? I thought we were
talking consumer PCs?
  #20   Report Post  
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crazy frog
 
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Default combining 2 power supplies

log on to siliconchip type in pc power supplies
into the article search box, it will take you to the new
article,s but not the old one for the dummy loads.
i asked them for it but thay wont to charge me.
i will see if ican fined it in my folders.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

www.siliconchip.com.au


What article?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

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Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

"crazy frog" writes:

thats what i read from silicon chip and have
done so and it works fine.
im useing a 200w one to power a 16/ch mixer
i have built in the last 2 years.
im useing a nother one power my modem
and network hub and some fans.


http://www.formfactors.org/developer...public_br2.pdf

This appears to be Intel's ATX specifications. It is not clear what
minimum load is required for proper regulation. Under "DC Voltage
Regulation", it says:

"The DC output voltages shall remain within the regulation ranges shown
in Table 2 when measured at the load end of the output connectors under
all line, load, and environmental conditions."

Later on in: "No Load Operation", it says:

"No damage or hazardous condition should occur with all the DC output
connectors disconnected from the load. The power supply may latch into
the shutdown state."

Loading examples never go below 1 A on +12, 0.3 A on +5, 0.5 A on +3.3.

So, it shouldn't blow up under very light or no load conditions, but the
exact values needed for proper operation may not be obvious.

And, the existence of this specification document doesn't necessarily
imply that all Far East ATX power supplies are fully compliant.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
  #22   Report Post  
Posted to sci.electronics.repair
Ian Stirling
 
Posts: n/a
Default combining 2 power supplies

lee wrote:
Thanks and I did my numbers:

I'm thinking a P4 9xx CPU and it draws around 100w alone, new display cards
(ATI x series) also draws a lot of power. More than 1 web site said hard
disks draws 25w so I use that in my calculation to be on the safe side.


Don't believe 'more than one website'.
Look at the specs for your drives.
The makers website will list exact startup currents.
  #23   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

i think you need some load to make it regulate properly

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

thats what i read from silicon chip and have
done so and it works fine.
im useing a 200w one to power a 16/ch mixer
i have built in the last 2 years.
im useing a nother one power my modem
and network hub and some fans.



http://www.formfactors.org/developer..._public_br2.pd
f

This appears to be Intel's ATX specifications. It is not clear what
minimum load is required for proper regulation. Under "DC Voltage
Regulation", it says:

"The DC output voltages shall remain within the regulation ranges shown
in Table 2 when measured at the load end of the output connectors under
all line, load, and environmental conditions."

Later on in: "No Load Operation", it says:

"No damage or hazardous condition should occur with all the DC output
connectors disconnected from the load. The power supply may latch into
the shutdown state."

Loading examples never go below 1 A on +12, 0.3 A on +5, 0.5 A on +3.3.

So, it shouldn't blow up under very light or no load conditions, but the
exact values needed for proper operation may not be obvious.

And, the existence of this specification document doesn't necessarily
imply that all Far East ATX power supplies are fully compliant.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.



  #24   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

the article im talking obout is for at power sups
and cannot fined it online, i had it someware
will try to fined it.

"crazy frog" wrote in message
u...
i think you need some load to make it regulate properly

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

thats what i read from silicon chip and have
done so and it works fine.
im useing a 200w one to power a 16/ch mixer
i have built in the last 2 years.
im useing a nother one power my modem
and network hub and some fans.




http://www.formfactors.org/developer..._public_br2.pd
f

This appears to be Intel's ATX specifications. It is not clear what
minimum load is required for proper regulation. Under "DC Voltage
Regulation", it says:

"The DC output voltages shall remain within the regulation ranges shown
in Table 2 when measured at the load end of the output connectors under
all line, load, and environmental conditions."

Later on in: "No Load Operation", it says:

"No damage or hazardous condition should occur with all the DC output
connectors disconnected from the load. The power supply may latch into
the shutdown state."

Loading examples never go below 1 A on +12, 0.3 A on +5, 0.5 A on +3.3.

So, it shouldn't blow up under very light or no load conditions, but the
exact values needed for proper operation may not be obvious.

And, the existence of this specification document doesn't necessarily
imply that all Far East ATX power supplies are fully compliant.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header

above
is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.





  #25   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

i found the artile, its from december 1998
silicon chip.
on front page is has make use of that old pc
power supply.
min load 47ohm 1 watt resistor, ive tested it up to 100ohm
and is ok.

"Sam Goldwasser" wrote in message
...
James Sweet writes:

There's a lot of wattage inflation these days, following the stereo
equipment makers in the 80s. The fact of the matter is that if you
have a *quality* 300 or 350W power supply, it should run just about
anything you can fit in the computer. I've measured a number of
computers with a power analyzer and I have yet to see one which draws
more than 250W from the wall under full load, most typical single CPU
computers are down around 160-180W even with multiple hard drives.


Don't fight it. People think that adding power supplies multiples the
speed of the PC by the number of power supplies added. No way to talk
them out of it.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.





  #26   Report Post  
Posted to sci.electronics.repair
Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

"crazy frog" writes:

i found the artile, its from december 1998 silicon chip.
on front page is has make use of that old pc power supply.
min load 47ohm 1 watt resistor, ive tested it up to 100ohm and is ok.


So what? Does it say the specification allows for that high a resistor
or just that someone did a project and it worked, and you did a project
and it worked? The article doesn't appear to be archived, so are you
going to share what it says?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

"Sam Goldwasser" wrote in message
...
James Sweet writes:

There's a lot of wattage inflation these days, following the stereo
equipment makers in the 80s. The fact of the matter is that if you
have a *quality* 300 or 350W power supply, it should run just about
anything you can fit in the computer. I've measured a number of
computers with a power analyzer and I have yet to see one which draws
more than 250W from the wall under full load, most typical single CPU
computers are down around 160-180W even with multiple hard drives.


Don't fight it. People think that adding power supplies multiples the
speed of the PC by the number of power supplies added. No way to talk
them out of it.

  #27   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

i sed i tested it up to 100ohm.
if you dont beleave me, just bloody try it.

look i have done it and it works.
the ****in aticle is in my hand.

if dont beleave me then, its youre bloody
loss.










"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

i found the artile, its from december 1998 silicon chip.
on front page is has make use of that old pc power supply.
min load 47ohm 1 watt resistor, ive tested it up to 100ohm and is ok.


So what? Does it say the specification allows for that high a resistor
or just that someone did a project and it worked, and you did a project
and it worked? The article doesn't appear to be archived, so are you
going to share what it says?

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

"Sam Goldwasser" wrote in message
...
James Sweet writes:

There's a lot of wattage inflation these days, following the stereo
equipment makers in the 80s. The fact of the matter is that if you
have a *quality* 300 or 350W power supply, it should run just about
anything you can fit in the computer. I've measured a number of
computers with a power analyzer and I have yet to see one which

draws
more than 250W from the wall under full load, most typical single

CPU
computers are down around 160-180W even with multiple hard drives.

Don't fight it. People think that adding power supplies multiples the
speed of the PC by the number of power supplies added. No way to talk
them out of it.



  #28   Report Post  
Posted to sci.electronics.repair
Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

"crazy frog" writes:

i sed i tested it up to 100ohm.
if you dont beleave me, just bloody try it.

look i have done it and it works.
the ****in aticle is in my hand.

if dont beleave me then, its youre bloody
loss.


And you've tried it on how many different manufacturer's power supplies?

You can contact me via the link below.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
  #29   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

yes i have

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

i sed i tested it up to 100ohm.
if you dont beleave me, just bloody try it.

look i have done it and it works.
the ****in aticle is in my hand.

if dont beleave me then, its youre bloody
loss.


And you've tried it on how many different manufacturer's power supplies?



You can contact me via the link below.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.



  #30   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

how do i send the pages of the artile.
how do attach them.
do you have a email address to send them.
like a hotmail.

"crazy frog" wrote in message
u...
yes i have

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

i sed i tested it up to 100ohm.
if you dont beleave me, just bloody try it.

look i have done it and it works.
the ****in aticle is in my hand.

if dont beleave me then, its youre bloody
loss.


And you've tried it on how many different manufacturer's power supplies?



You can contact me via the link below.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header

above
is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.







  #31   Report Post  
Posted to sci.electronics.repair
Sam Goldwasser
 
Posts: n/a
Default combining 2 power supplies

"crazy frog" writes:

how do i send the pages of the artile.
how do attach them.
do you have a email address to send them.
like a hotmail.


You contact me via my Web site and I'll reply with a valid email address.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
  #32   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

ok but im not soure if silicon chip will
let send copies of ther aticles based on copyright
laws.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

how do i send the pages of the artile.
how do attach them.
do you have a email address to send them.
like a hotmail.


You contact me via my Web site and I'll reply with a valid email address.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above

is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.



  #33   Report Post  
Posted to sci.electronics.repair
crazy frog
 
Posts: n/a
Default combining 2 power supplies

the silicon chip aricles are copyright
i cannot send it.
but just take my word for it.
47ohm to 100ohm.
or you will have to log on to them and
ask them.
sorry about that.

"crazy frog" wrote in message
u...
ok but im not soure if silicon chip will
let send copies of ther aticles based on copyright
laws.

"Sam Goldwasser" wrote in message
...
"crazy frog" writes:

how do i send the pages of the artile.
how do attach them.
do you have a email address to send them.
like a hotmail.


You contact me via my Web site and I'll reply with a valid email

address.

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header

above
is
ignored unless my full name AND either lasers or electronics is included

in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.





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