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Jim Yanik Jim Yanik is offline
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Default Yet another bulging-capacitors replacement

"Arfa Daily" wrote in
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"Jeff Liebermann" wrote in message
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On Mon, 30 Aug 2010 05:35:00 -0400, JW wrote:

On Fri, 27 Aug 2010 20:19:44 -0700 Jeff Liebermann
wrote in Message id: :

I don't believe it. The winner of the power hogging consumer CPU
contest was the DEC/Intel Alpha 21364 (EV79):
http://en.wikipedia.org/wiki/Alpha_21364
which burned 155 watts. Itanium II came close with 130 watts (per
core).


Check again.
http://ark.intel.com/Product.aspx?id...0&spec-codes=S
LBMX 185W! Gotta love that price as well.


I stand corrected.
http://techreport.com/discussions.x/18445
Some of the reader comments are rather interesting. Still, with any
of these "powerful" processors, a conventional air cooled machine is
going to have a very hot breath and a rather large power supply. I
just don't see this kind of power dissipation in a "dedicated game
machine". Measuring the AC mains power consumption should settle the
matter.

--
Jeff Liebermann



Have you any idea just how much processing power it takes to run a
user-interactive story in real time, and then to 3D render the
graphics in real time ? Do you think that they rate the 12v PSU for
23.5 amps in one version, and 32 amps in the other, for fun ? Those
are not real questions, because I know full well when you stop and
think about it, you know the answers, Jeff.

I've just looked at the rating plate on the bottom of one of the
cases, and it is 240v (nominal UK line voltage) at 1.8 amps. I make
that a maximum input power of around 430 watts. It's a switching PSU,
so I reckon that we can rate that as being at the very worst 80%
efficient, so that's still 345 watts potentially going somewhere. I'm
prepared to go with 45 watts into ancillary circuitry on the board,
which still leaves around 300 watts going somewhere.


that assumes that all the power of the supply is actually used.
I'm sure there is some reserve capacity there.

"max input power" is not "actual used power".

Perhaps I'm being
naive, but my best guess is that it's disappearing into the two bloody
great BGAs which the manufacturers are trying their utmost to
heatsink. If you try to run one of these machines with the heatsinking
not in place, it goes into thermal protect in about 5 seconds - and
all it's doing then is booting. The heatplates on the BGAs are at this
point hot enough to take your fingerprints off ...

Nope, I'm pretty sure that these two puppies are good for 150 watts
apiece, when the machine is doing some real work.

Arfa





--
Jim Yanik
jyanik
at
localnet
dot com