Awhile ago some friends asked me to have a look at their machines. Now I'm at a stage when I am sure both are experiencing serious hardware problems - maybe the motherboards of both are partly fried - but I am not sure how to diagnose them. I will give a description of the problem for each.
#1 - the Vista machine.
I haven't got the exact hardware details for it, only the exact mobo model - Gigabite GA-P35-S3G Rev 1.0, socket 775. It is relatively new, quad core CPU, 2GiB RAM. The computer has been shutting down spontaneously, and was displaying strange sickly patterns on the screen. I installed Everest on it and it showed the CPU was around 60 centigrade and the Video card was in the 90's. Opened the box, say there was a medium dust problem and poor ventilation. Told them to stop using it and bought 120mm fans for the box, then cleaned it thoroughly and installed the fans. When I turned the computer on with the box open after that, I saw that the CPU fan was not working, so I plugged it into a different power socket on the mobo and made sure it was working. It seemed to improve for awhile (video card was only 60 centigrade now), but the lines on the screen didn't go away. I also noticed, after awhile, that most of Everest sensor icons were gone, in the system tray display. I tried configuring Everest to show them, but the options were missing - like those temperature and fan speed sensors had just vanished. Now it usually will not start or start and reboot. When I went into CMOS Setup there were ugly artifacts on the screen to the point that I couldn't see the menus clearly. My guess is that either the video card (one of those new ones that have their own fancy cooling fans) or the motherboard or both are partially baked, but I have no way of being sure.
#2 - The XP machine
It's around 4 years old, mobo - Intel Desktop, LGA775 IPIGC-96 Rev 1.02. Single core Intel CPU. It was experiencing a serious overall slowdown. I tried removing malware, even instructed them how to go through the malware cleaning procedure on G2G. Installed Everest, it showed that the chipset was pretty hot, so I installed two 120mm case fans (they only had a 1 80mm back fan before) in the box and cleaned it thoroughly. It all didn't help, so I reinstalled XP for them, installing all security software and SP3 before installing the mobo LAN driver (so that it would go online well protected). But the problem started again after a day or so (or maybe it never went away, I'm not sure, though, when I was installing the system and programs the computer was working OK). Now it's so slow they say they hardly use it at all. A strange thing I've noticed about it: though Everest shows that the chipset is at around 80 degrees centigrade (though it jumps up and down pretty wildly) and the CPU it at around 40, when I check the sensors in BIOS it tells me the CPU is boiling (80 and even above 90 degrees) and the chipset ot around 40. One thought I have on it is that maybe the CPU fan needs to be replaced. It seems it sometimes revvs up and them slows down again, you can actually hear it doing that.
So, my question is: how do I troubleshoot them? On the Vista machine, I could try replacing the video card with a good one (would it not damage the good card if the motherboard in the Vista machine is also faulty, and that's possible - one possible symptom, I think, is the disappeared sensor icons); then test the card in a working machine (would it not harm that machine if the card is faulty?).
If the card is working well in another machine, then, would it be safe to say that the MB is bad?
Since it often doesn't boot at all, I could try using a POST card - gonna get mine next week, I think : )
As for the XP.... I dunno. My inexperienced senses are telling me the MB is probably gone. I could start by comparing the output of another hardware monitoring program to that in CMOS Setup.... maybe replacing the CPU fan and drilling holes at the front of the box where I installed one of the case fans - it doesn't seem to be too efficient since the panel in front of him is almost completely sealed - nowhere to draw air from.
Any ideas and insights are welcome.