Problem with a Coolermaster PSU + Gigabyte Mobo

closeratio · 6 Jan 2010 at 19:08

I helped my friend build a new computer a few months ago which he was going to use to run ProTools on (he was starting a course at Staffordshire Uni, as it happens). Anyway he got a pretty decent setup, listed below (if my memory serves me right):

Intel Core i7 920 CPU
Noctua Dual Fan CPU Cooler
Gigabyte EX58 UD5 Mobo
Coolermaster Cosmos RC1000 Case
4 Gigs of Corsair DDR3 Memory
Coolermaster Silent Pro 500W PSU
+ The usual Optical Drive, Two 1Tb drives for data and stuff, and a 150Gb Velociraptor for the OS.

As you might be able to tell, he wanted the rig to be pretty silent as he was going to use it to record instruments and vocals. A few days ago, he came to turn it on and nothing happened, as in nothing at all. No signs or life or anything. The night before it was fine and it didn't show any signs of bad things happening.

To try and diagnose the problem, he plugged in the PSU from another computer he had running (A Hiper 550W, I believe) and the computer turned on fine, which led him to believe it was the PSU at fault. He'd already tried a different power lead as well with no joy.

Today we drove to a local computer shop, RMA'd what we thought was the faulty PSU and got a new one, identical to the faulty one (the shop wouldn't allow him to have a different one, but nvm). As he was plugging the new PSU in now, the same thing's happening, except that the mobo does show signs of life in that when the large 24pin mobo cable is plugged in, the lights on the mobo light up for a short time before going off again. But as before, the power switch does not turn everything on as it should.

He then tried the new Coolermaster PSU in the computer which had the Hiper PSU in it and it turned on fine, so to temporarily sort the problem, he's swapped the two PSUs around, though ideally it'd be best if the silent Coolermaster one was back in the Comp that was running Pro Tools. Does anyone have any idea why the Gigabyte mobo doesn't seem to like having the Coolermaster PSU plugged into it? I find it odd that it won't work in this mobo, but it will work in an older one (implementing a P35 chipset), and that Hiper PSU will work with the Gigabyte mobo.

Cheers

closeratio · 6 Jan 2010 at 20:32

Update: He's just rang me and told me some other interesting information. With the old Hiper PSU plugged into the newer comp, it won't on if it's unplugged from the wall and then plugged in again. In order to turn it on, you have to unplug the 24pin mobo lead and plug it back in again. However if he just leaves the comp plugged in, it turns on fine without any hassle.

The only thing I thought could be the problem would be a flat mobo battery, but I think that's unlikely to be the problem. Hopes this helps. Atm I'm more confused than I was to start with lol.

Tiamat21 · 6 Jan 2010 at 21:06

Hmmm, shouldn't do any harm swapping the mobo battery.
Their just normal cr2032 batteries and are about 2quid each.

Otherwise try reseting your CMOS?

closeratio · 6 Jan 2010 at 22:43

Thanks Tiamat, I'll let him know. I thought about that as well, I guess it's worth a try. He hasn't overclocked it at all so it shouldn't be an issue with regards to resetting the CMOS.

closeratio · 7 Jan 2010 at 16:30

Ok problem solved, and the thing that was causing it was actually the case of all things. In case anyone has this problem in future, I'll post the cause below:

Basically a week or so ago, when my friend was taking a USB flash drive out of one of the front USB slots on the case, Windows came up with an error message basically saying that there had been a surge on one of the USB ports. He thought nothing of it at the time, as the next time he turned on his computer, it seemed fine.

However whilst inspecting it today, he found that the central plastic thing in the USB slot on the case which the four wires are connected to had actually been pulled off (if you look at a USB port on yout comp now, you'll see what I mean), presumably when he pulled his flash drive out. This caused two of the wires to short, which is what produced the surge message in Windows. When he unplugged the USB header form the mobo, the computer started fine without any problems.

Whether this was because he pulled the flash drive out a bit too hard (which sounds daft, so I doubt that's it) or perhaps even shoddy workmanship by Coolermaster, it's unclear. Only problem is that two of the four front USB ports on the case don't work now, but at least the main problem's solved.

Why the computer wouldn't start when the USB port is shorted is probably some safety measure which the motherboard implements to stop it damaging itself. An odd situation though, indeed.