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[email protected] bruce2bowser@gmail.com is offline
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Default PC desktop main fan won't turn on after rooting around insidewith cabling

On Thursday, June 7, 2018 at 1:26:39 AM UTC-4, Arlen Holder wrote:
There are 4 fans:
1) Attached to the back of the tower is the now not-working ~3x3" fan
2) The sound card GPU has a working fan (attached to the GPU)
3) The motherboard CPU has a working fan (attached to the CPU)
4) The power supply has its own working fan also (inside the power supply)

When I added a few disks and cleaned out the dust inside, I disconnected
all the SATA power cables and bought af Molex-to-SATA adapter, where, when
I put it all back together and powered it up, the main #1 fan above isn't
working anymore.
http://img4.imagetitan.com/img.php?image=17_fan.jpg

I've been using the computer for a few days without that main fan.
Googling for how to check the temperature, I installed and ran Speedfan.Exe
with the side cover removed.
http://img4.imagetitan.com/img.php?image=17_clipboard015.jpg
I think the only tab in Speedfan.Exe that is useful is "Readings".
- Fan1: 0 RPM, Fan2: 1236 RPM, Fan3: 0 RPM, Fan4: 0 RPM, Fan5: 0 RPM
- GPU: 73C, Temp1: 45C, Temp2: 29C, Temp3: -2C, Temp: 0C
- HD1: 43C, HD2 44C, HD0: 40C
- Core 0: 37C

The only thing I see 'wrong' perhaps is that the graphics card has a 6-inch
set of black and white twisted wires that aren't connected to anything on
one end as shown below.
http://img4.imagetitan.com/img.php?image=17_computer_1.jpg

I don't remember if that set of wires was connected or not, so I left it
unconnected. Plus, why would a graphics card control the "main" fan anyway?
http://img4.imagetitan.com/img.php?image=17_computer_2.jpg

The motherboard & graphics according to CPU-Z from cpuid.com a
- Gigabyte Technology Co. Ltd., Model EP43-UD3L
- Nvidia GeForce 8500 GT, ASUSTek Computer Inc., G86, Revision A2

The "sensors" reading of the GPU-Z software from TechPowerUp says:
- GPU Temperature 73.0C
- Fan Speed 40%
http://img4.imagetitan.com/img.php?image=17_clipboard0219.jpg

The fan seems to only have two wires going to it which come from a Molex
connector with original pigtails, so the fan has power I'm pretty sure (I
haven't taken it out yet becuase I think the two wires coming off the
graphics card are what caused the fan to stop.

Any advice for what makes the main #1 span spin?
(Could it be the twisted pair of wires coming off the graphics board?)

If the machine runs without the fan, will it shut off when it gets hot?


The surface that you set a computer on is important. If the surface is dust-free and porous, it will allow more air to circulate around the cpu and power processor, keeping things cooler.
But if you put a computer on the bed or the sofa with plenty of fibers, the system could overheat easier and fibers could clog everything, etc...