System crashes, could it be the motherboard?

[VT_Hokie]

my system specs:

1.4 GHz AMD Athlon CPU
512 MB RAM
NVidia GeForce2 GTS
Windows XP Home Edition
Asus A7A266 motherboard
SB Live 5.1


my computer has been crashing only after about 5 minutes of use. either: (1) the video gets cut off and my monitor is receiving no signal, or (2) the screen turns into a crosshatching of random colors. also, any music that is playing locks up. i cannot turn off my computer via the front power switch, only the one in the rear. if i try to reset my computer, it resets, but doesn't post and i don't get a monitor output. i'll come back to it the next morning, when the machine is cold, and it will turn on and work for about 5 minutes before crashing again.

i have eliminated several possibilities. i have replaced all the case fans and run the "big fan blowing into the open case" test. i have also checked the temps in the bios, and they are not abnormally high. heat is not likely the culprit.

also, i first thought this was a video card problem, but i have run two other video cards and the problem still exists, so the video card is also not likely.

based on this info, do you think this could be a motherboard problem where i'd have to replace it? i have not made any hardware changes to the system since i bought it 3 years ago. i'm hoping to get this fixed so i'll have my computer before school starts.

thanks.

[LadyGrey]

Hi VT,
If you haven't already the first thing I would do is run all antivirus,adware,spyware programs, do an online scan too.
The Guru's will be around shortly I'm sure but have you ruled out the monitor as the problem yet? Have you blown out the heatsink and fan with air on your CPU? Dust can be a major problem. Have you checked all your connections? Just some of the things I would try in my limited experience. Keep your chin up I'm sure someone here will have the right answer!
LG;)

[VT_Hokie]

thanks for the reply.

i did run all the antivirus and spyware programs, and i did clean out all the dust from inside my case. it isn't the monitor either, because i've tested two different monitors with the same results. the CPU temp according to the bios is around 57 C, which i didn't find dangerously high.

i guess i've done more than i thought to try and solve this problem.

[ziba-june]

Have you checked your power supply yet? Mybe your power supply is going bad and it give you these kind of trouble. While you are there check for bad capacitors too.

[LadyGrey]

VT, I seem to remember most of the guru's here saying that anything over 50C is not a good thing. My CPU has a max temp of 80C but I wouldn't ever want to test that out! If you can keep your CPU under 45C is would be great but AMDs always tend to run just a bit warmer. Mine runs about 46-47C with the case temp around 42-43C and I seem to do ok like that.
Ziba has a good idea, check it out, can't hurt and at least you could rule that out.
Pete has some pictures here of what bad capacitors look like.
Petes Pages (http://www.pcguide.com/vb/showthread.php?s=&threadid=25482)
Hope that's some help.
LG;)

[Paleo Pete]

Check for bad capacitors and I think flaky RAM might be a good possibility too. My first thought was video card, but 3 different cards shouldn't have the same symptoms, so my next guess would be faulty RAM. Either try a good memory tester or try different RAM.

From what you posted, your CPU is running a little on the warm side, it might be a good idea to pull the heatsink and apply new thermal compound, but I don't think heat is the main issue. It's not into the danger zone yet, but too close for comfort if it were my machine. I like to see them stay below 50C. It's been a while, but I think I have this one set to alarm at 60C and shut down at 65.

[VT_Hokie]

i ran a memory tester and no errors were found, and i inspected the capacitors on the motherboard and they all seemed fine, using the photos in the other thread as a reference. i had previously ordered a motherboard that just came in today, and i'm wondering if you have any other ideas before i take the time to swap it out. i don't think the power supply has gone bad, because i haven't added any new hardware to increase the load of the system.