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Thread ID: 121252 2011-10-18 03:36:00 What possible reason for CPU fan not starting? BBCmicro (15761) Press F1
Post ID Timestamp Content User
1238224 2011-10-18 06:46:00 Maybe the fan control circuitry on the motherboard has failed.

If you have a multimeter or oscilloscope you could check for power and\or PWM outputs from the fan header...
Agent_24 (57)
1238225 2011-10-18 07:21:00 I find it hard to believe that the MB has died, and in such a minor area...

If I measure the pins there won't be any voltage on them, I'm betting. I might bare the wires on the replacement fan and measure them tomorrow.

I have the feeling it's software/firmware related.

Probably a red herring, but there were driver problems I couldn't resolve. Everything sweet in Device Manager, but there was a continuing series of 'driver installation' hangups. They were different each time I booted. Often it was 'unknown device', other times PCI bridge, IEEE 1394, SM - sometimes several together. The odd thing was that the heading said 'Installation successful' even though the hourglass (actually spinning circle) went on forever.
BBCmicro (15761)
1238226 2011-10-18 07:37:00 Can I offer some advice --

Being a reseller myself ------ DONT PISS ABOUT WITH IT :stare:

Take the New fan and plug it into another PC, see if it goes. Assuming it does Forget about testing the board etc, and heres why --- the more you muck about with it, the more chance they will say you may have caused the problem and you voided the warranty.

If you tested the fan and it works on another PC, simply call them- tell them the problem (fan not working) the fan was plugged into another PC and it fires up. Also mention the problems with the drivers .

You suspect the mother board has a fault -- NOW if they are any good, they will tell you to send back the motherboard (and maybe the CPU Fan/Heatsink), they will test it, and assuming its new (which going by the way the original post was written it is) it SHOULD be class as DOA - (dead on arrival)

No questions asked,or waiting for weeks, they should simply replace the board on the spot with a new one. Theres no need for you to wait for it to be sent back to the repair center, as it was faulty from the beginning.
wainuitech (129)
1238227 2011-10-18 09:07:00 Thanks Wainui - it sounds like good advice BBCmicro (15761)
1238228 2011-10-18 09:50:00 Sounds like a faulty fan to me, if everything else is working. Best to get a replacement, unless you fix the issue of course. goodiesguy (15316)
1238229 2011-10-18 19:26:00 I took Wainui's advice and plugged the fan into another MB (GA-P35c-DS3r) It worked fine . That's the MB I'm using right now

I also checked the new rig this morning to see if anything changed overnight . Nope, the fan still wouldn't go

So it's looking like a faulty MB alright .

I forgot to mention that besides the fan not working and the random driver installation messages the new rig was very slow . I had run the memory check early on and it passed OK
BBCmicro (15761)
1238230 2011-10-18 20:31:00 Well, I talked to Computer Lounge and got a good response - MB will soon be winging its way north BBCmicro (15761)
1238231 2011-10-18 20:45:00 They were good to me when I had stability issues as well, so far I'd reccommend them for their customer service.
Seems like it's sorted but just my 2c on one point, you can plug 4 pin and 3 pin fans into each others headers safely and they will work, all that happens is the PWM speed control doesn't function. You could have tried a case fan header or a molex to fan adapter to prove the CPU fan no problem.
dugimodo (138)
1238232 2011-10-18 20:49:00 Of course (now that you point it out!) BBCmicro (15761)
1238233 2011-11-02 04:21:00 Update: I returned my brand new Z68 MB to Computer Lounge and they replaced it without fuss. (Couldn't get the CPU fan to go, other probs.)

Replacement MB fine. Booted into the old installation. No yellow marks in DeviceMgr. No random hardware detects. CPU fan goes

So it wasn't 'me' :)

(Thanks particularly to Wainuitech who told me not to stuff around
BBCmicro (15761)
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