Pine Technology Mach 4 KT400ANB Motherboard

Question

I have the above mentioned mb and it will boot up sometimes, and now it will not boot. Replaced case with 400 watt pwr supply, and since i did that it will send a video signal sometimes for only about 4 minutes while i try to reload OS, XP home, now i cannot get it to come on at all. It is an AGP 8mb video, my board only houses AGP or PCI.Please help any way you can [e-mail]