This is a strange problem which I have an idea what may be the cause of but I just want to make sure before I make any expensive purchases. Namely, my problem is that my machine has recently started hanging during games and staying like that. No BSOD, it just loops the last second or two of audio and stays like that.
As far as I can tell, it's not a graphical error as if anything ever happens like a GPU crash, my second monitor goes black immediately and I get a BSOD on the main screen. I have a 260GTX and when I turn my machine on I usually bump the fan to 100%. A curious thing is, since I updated my driver the last two or three times, when I go to bump the fan speed up, it's always at 20% according to the counter on the nVidia control panel (Maintaining about 57C roughly on idle. When I move it to what should be 100% it reads 147% and when I click apply, nothing happens. I have to move the slider to 145% again and click apply a second time for it to go through.
I'm using a generic PCI network card because I burned out the onboard network controllers about a year into the life of the machine somehow.
My processor is a Q6600, the older hotter variant but I have a good after sales cooler that keeps it idling at about 30C-36C and it goes to load at about 40C-50C. Temperatures are taken from CoreTemp.
I do have recovery enabled but I have it set so it doesn't automatically restart so I can take down BSOD codes.
Before these problems, I was getting bad data pool errors which are indicative of a hard drive or ram failures but after doing a scan disk check and a complete reinstall of Windows XP Home I haven't gotten them again. I've also replaced the ram and the same problem kept popping up though then again, said ram was also left in a static proof bag for about a year and a half and I still kept getting the bad pool error.
I've had my machine for about, three years now and over the last year the start up has slowed down randomly. For example, some days when I switch my machine on, it'll take no less than two or three minutes to boot up when other times it'll boot up in about a minute and a half. Randomly to that, a fourth hard drive in my machine will sometimes not appear and I need to have it running for about ten minutes before starting it again and then it appears.
Which is leading me to believe that it's most likely a problem with the motherboard. The motherboard is an MSI P6N Diamond and of the reviews I've read, it was pretty good and it had plenty of SATA connectors. There has been a BIOS update for it but I've held off on installing it because if it ain't broke, don't fix it and generally, I've had nasty problems from updating the BIOS of computers before so I'm quite hesitant to do it.
My power supply is a Tagon Toughpower 650W PSU and I've been told that the problem might be that it's reached the end of it's lifespan and that replacing it could fix my problem. I was thinking of getting a Corsair 750W and swapping out the 260GTX for a 470GTX but I want to make sure this same problem isn't going to keep following me along.
I'm with jack_attack. The problems you describe are most commonly caused by RAM problems. Performing an overnight Memtest86+ test to check for RAM errors would be the first thing to do. Crucial Ballistix RAM doesn't exactly have the best reliability record.