MSI-Athlon 2100+: Random crashes

[sychopike]

hey guys, my problem is that when i open a bunch of programs or run 3d mark03 my computer will crash to a restart. my cpu stays between 30-40(max)C and motherboard 30-40C also. i've got 3 fans, 2 running at 2700RPM and one at 4800RPM. On my Athlon 2100+ (Palomino/running FSB at 100mhz/1300MHz clock) is a thermaltake volcano 9. I have the cpu at 100 FSB for stability... should be at 133 right? I had this problem about 3-4 months ago when i was running an Asus A7N266-VM, i didn't get crashes on it until after i installed my VisionTek 9800 pro128mb, but it got to the point where i would start up and it would crash so i replaced the motherboard with the MSI K7N2 Delta-ILSR and the problems went away until now. oh when i had the Asus i disconnected my Radeon and used the Geforce2mx that was built in and the same problem came up, just took longer to happen.
System Specs: I'll list the things that the problem prolly lies in first
power- generic 350watt P4-ready PSU (fluctuation in voltages) i dont know much about PSU's
RAM- Corsair ValueRAM 2x256mb (Dual Channel)
Grafix- VisionTek 9800 Pro 128mb 8x agp/ fast writes enabled/ 64mb in BIOS
Running WIndows XP Home (Sp1)
If you need more specific info just tell me what you need and i'll get it. it pisses me off that it was fixed when i replaced the mobo, but has come back again. any help would be nice.

 

[Zepper]

Random crashes are usualy due to flaky PSU or memory. Have you run Memtest86 and/or M$ memory tests (both free DLs, go get 'em)? Reseat your memory and try a good brand PSU. And I think ATI recommends you use a pretty sturdy PSU when running that vid card.
.bh.

 

[sychopike]

ok i'll try that thanks for the help

 

[car24fan]

Zepper where do you get the memtest86 programs. and what is PSU?

 

[Zepper]

Memtest86.com, duh... PSU=Power Supply Unit
.bh.
You're welcome!