Why my PC crashes when I convert files or create DVD's???

[Ktulu]

Howdy People.

Don't know if this problem has already been debated before, because it may be anything and nothing.
I use different tools for my video projects. Both Premiere and Premiere Pro, Virtual Dub, Tmpeg Enc. and others. Recently I'm occuring with crash problems, i.e. all of a sudden the PC freezes and the only way to continue is the reset button. This happens when I try to convert avi files into mpeg, and, mainly, when I try to convert mpeg files into DVD's. I use Ulead DVD Movie Factory 2 as well as Encore DVD. This problem is really pissing me off, because I'm always at the same point (around 72% of the project I'm currently working on with Ulead, and 5% on Encore's project); mostly, I'm very late with the working schedules.
I use AMD Athlon 1800+, ATI All-in-wonder 8500, 256 Mb ram, 2 HD drives (40 + 80Gb, 30 Gb free space). Anybody knows what is going on? I hope not to have to format everything .....

[johns0]

Yes this problem has been discussed many times and its always a few things that can cause crashes and it could be bad ram,faulty power supply,driver conflicts,viruses etc..,you have to narrow down whats causing it and do some testing,with ram d/l memtest86 and run that overnight,for psu problems get a good quality brand of over 400 watts and do the usual virus scan and driver confict tests.