I've recently been having a problem when i try to play any demanding games or any program that takes up a lot of memory. there is a "restart" click noise then about 5 seconds later the computer totally freezes up and i have to hard reboot. i have tried testing the ram with memtest86, the hard drive with WD lifeguard diagnostic, have replaced all the drivers, fixed the registry and have cleaned out the case a few times with no luck

My setup:
intel pentium d 3.4ghz processor
radeon 9800 pro graphics
a 160 gb western digital blue caviar hard drive
1.5gb of corsair ram (256,256,1028 sticks)
Mother Board is an Asus p5p800-vm

Thanks

I'd say this is the fault

Best advice would be to backup all user data to external media (DVD or USB drive)
Then consider purchasing a larger Harddrive (as you are a gamer) and ideally Sata (if your motherboard supports a Sata connection) Just found out it does, from h e r e

I'm thinking minimum 250Gig Sata Hdd
Ideally, you might think about updating the entire computer though, as your graphics slot is only AGP 8X not real good for gaming

IF you opt to replace the hard drive (not everyone has a lot of $ these days for a new system), you should consider getting another 1 GB stick of ram to match the one you have. This will allow you to run Dual Channel memory - you'll have MORE and FASTER.

re the hard drive: have you done a defrag lately?

Well i replaced the harddrive with a 160gb WD sata hardrive and it fixed the random freezes however my cpu was behaving really slowly and i found out it was underclocked (133mhz x 17)
so i set it back to standard factory setting (200mhz x 17) and this seemed to make it fine for about a day and then my brother kept getting random restarts when he was playing counterstrike source. I tried underclocking my graphics card a bit and this fixed it for a while but now the system seems really laggy with little cpu usage and ram usage. i really do not know what the problem is.

Oh, well it was like for like then. Probably would have been best to go a little higher (but I suppose that's the $ factor)

Run CCleaner, and test again

Change the CMOS battery

Most likely your CMOS battery is dead and is not saving your BIOS data for your CPU, memory etc. The battery is on the motherboard, usually 3.3V. Changing that should fix the problem.

i tried using CCleaner with no luck. im still getting artifacts and restarts. i dont think it's my CMOS battery because my BIOS settings havent changed and im not getting the warning on startup

CMOS / Memory Diagnostic / Artifact Scan

If your CMOS battery has passed ( has been tested with a Multimeter or replaced) try running a memory diagnostic from a bootable CD, using either Memtest86 memtest86.com/ or with a Ubuntu x86 boot CD ubuntu.com/getubuntu/download/ or a Windows 7 Recovery CD. If you cannot create the ISO for the boot CD you can download a program called ISORecorder over at isorecorder.alexfeinman.com/isorecorder.htm to create a bootable CD from the ISO file. If you're getting artifacts on the video card, run the ATITool over at techpowerup.com/atitool/ and run the Scan for Artifacts. See if any of those fail or not first.

Even though you replaced your hard drive, it never hurts to run a Diagnostic. For Western Digital hard drives download and create the boot CD from the ISO file and run the diagnostic tool support.wdc.com/product/download.asp?level1=6&lang=en for Seagate hard drives use the Seatools Diagnostic for DOS boot CD seagate.com/www/en-us/support/downloads/seatools/

Good luck.

Tested

I Changed the CMOS battery and tested all three things. the only problem i had is with the graphics card. Here is the last line of the log:
2002-01-01 00:18:38 I Artifacts detected after 08:52.12. 127598 pixels don't match.
There were more artifacts from 3:17.75 to 08:52.12.

Graphics / Artifacts

If you are getting Artifacts, it usually means the graphics memory or core has been damaged and the card needs to be replaced. Ideally, the solution would be to remove the damaged card and replace it with a reliable working spare and run the Artifacts scan again. If the spare card shows no signs of Artifacts, it is safe to assume that you need a new Graphics card.

I notice that your date and time are not setup properly. Check your BIOS settings.

I have tried replacing the graphics card with a nvidia agp 7600gt card and it fixes the artifacts however im still getting random 6-10 second freezes and system restarts.