Ok for starters made my computer by myself and it was working for the longest time and then I decided to get a new CPU.. I was going from a Celeron D 3.3ghz to a Pentium D 2.8ghz.. Mobo is a Mach Speed P4MSD-800.. It didn't work got nothing on the monitor screen.. I put the celeron back in and it worked so I was thinking it could be the bios needing to be updated.. So I tried changing the mobo, P/S worked with celeron but not the pentium.. I contacted Mach speed and they said that they are compatible.. Any ideas I'm stumped and its not the graphics card tried the on board one and a agp.. HELP!! :confused:

So I found out that I had to take the bios battery out and put it back in after 10 min and turned it on and boom back in business.. thanks anyway:D