First off, apologies if this is in the wrong subforum. I was looking for just a general Desktop PC subforum but there didn't seem to be one, so Windows 7 seemed to be the next best choice.
I bought a rig from my friend a few months back, and its been working fine until lately. Over the past week or so, I've noticed that the computer seems to shut itself down randomly. Sometimes it'll stay on almost all day before shutting down, other times it will only run for like half an hour before shutting down. There doesn't seem to be a discernible pattern to it that I can tell.
The power doesn't just immediately cut off (like it would if the power was suddenly unplugged), the screen will slowly fade away, almost as if the power button had been pressed and the computer was shutting down. Upon starting the computer back up, there is no "windows shut down unexpectedly" message, so it would almost seem that the system is shutting down correctly. There's nothing sitting on top of my case that may be pressing on the power button, and I've left the computer on when leaving for the day, and then come back home and its turned off. My room locks with a deadbolt lock so I know no one is coming in and shutting it down or something.
I was thinking maybe the CPU was overheating, but the CPU is water cooled so I wasn't sure how likely that was. I've been monitoring the CPU temp with Speccy and it's averaging at about 30C. I'm not sure if that's high or not, I've seen other posts where people mention their CPU temps are in the mid 20's. It seems like a water cooled system should be able to keep the CPU in the 20's, maybe there's something wrong with that water cooling system?
I've also seen in similar posts, the problem may be that the PSU is failing. Unfortunately I do not have a spare PSU to test this, and I don't believe I have my multimeter anymore to test voltages and whatnot.
Are my CPU temps too high, causing the system to shut down? Or is it more likely the PSU? I do believe I need to air dust the case, as I haven't done so in a while, maybe this is the cause of overheating or something?
I realize more information may be needed. I don't know the system specs off the top of my head (as I said, I didn't build it), but when I get home I can post more information regarding the system. But for the time being, can anyone make an educated guess and point me in the right direction?
General System information (may or may not be important):
OS runs off a 60GB SSD
All User files are kept on a separate 750GB HDD
1TB HDD for media storage
160GB WD Velociraptor for game storage
CPU is an AMD Quad Core, which is water cooled
2 ATI graphics cards that I believe are CrossFire'd together
^can post more specifics on the components when I get home and can take a look at them