Alright...just went out and spent $600 for a new MSI 845 board, 2.4 processor, and 512MB of 400DDR RAM. Formated main drive and put WIN98SE(yes that...can't afford any better yet) back on clean drive. Had hours of problems with crashes and yes..it shut off again! Guess what...removed my ATI Radeon card(like you already suggested) and it stopped shutting off. All I had to put in it was a creative labs 3D Blaster PCI....it seems fine it rendered my troubled video with out problems.
My question...I am using NERO 6 for DVD authoring and it seems to crash. I am wondering if there are surefire settings I can use in the BIOS and OS to run top-notch? Thanks for your help!