Mobo or PSU?

cocodaclown · 3 Nov 2007 at 11:58

Hi, just bought a load of stuff off OC. Among all of that I have a OCZ 700w gXs psu, Artic cooler and a Gigia-byte GA-P35-DQS mobo.
What happened is this. I put it all together, adding my new Artic fan, added power, started... and the fan didnt work. OK I thought. I took off fan and added stock fan. Fan didnt work. If I flick the fan to spin it, it works (not very well, but hey, its a stock). After that it seemed ok for the last 2 days as I tried to remember to RMA the Artic. However, this morning, I turned on my comp as usual, everything booted correctly, but the comp seemed a bit sluggish. I tried my desktop monitoring utilities to see where the system lag was, and it shows no CPU activity and no fan activity. I check inside the case and the cpu fan isnt working :eek:

So I have desktop, I had just been onto a MMORPG I play, listening to the online radio and ive done all that without a cpu fan :confused:

I rebooted, the system boots onto desktop but still the fan doesnt work (without a manual spin to set it off)

So now I have to think. Is it the PSU thats not supplying the correct power to the mobo (maybe a 12v isnt working correctly) or is the mobo not working right cos it wont pass power to the fan?
Any help will do as it was over £1200 I spent and I dont want to see it down the pan... thx all

Cob · 3 Nov 2007 at 12:52

The fan will be on a speed controller, and will only come on when needed.

You can disable the fan controller in the PC Health Status menu in the BIOS if you wish to.

cocodaclown · 3 Nov 2007 at 13:18

oh if thats the case then ty. However (famous last words eh?) the fan has been working these last 2 days and its just today that it hasnt been on. Thats not to say that you are wrong Cob, just that I now dont understand why it was and it now it isnt.
Just to check if it was a psu or mobo thing, I changed the cpu fan to a different mobo plug (4 pin header) and it works (yeah I know, the fan should work because its not connected to the fan controller now). It spins at a steady 1300rpm (it was 680 before - even when playing BF1942 yesterday) and my cpu temp has dropped from 28 to 19c.

Cob · 3 Nov 2007 at 13:21

Well on a different header it will be running flat-out at all times.

It's just a case of whether you want cooler temps and a flat-out fan, or average temps and a slower fan. If it's noisy at full speed then the fan controller is a great idea. If it's quiet at full speed then you may as well disable the fan controller in the BIOS and let it run flat-out.

cocodaclown · 3 Nov 2007 at 14:14

Well I took your advice, I disabled the fan controller in the BIOS, put the fan back on the CPU header and rebooted. The fan stopped working instantly. So thx Cob, but unless you can think of anything else I suppose i've got to presume my mobo cpu header is faulty.

Thx again. If anyone else has an idea please chip in