My Dell laptop won't turn on. Please help

[Swat5444]

Hello, I've got a Dell laptop XPi p75D. 810mb harddrive. Active matrix color screen, and 75mhz pentium processor. The laptop will not turn on. It just quit one day. The AC adapter was tested and it works fine. The battery was tested and it is holding a charge. The hardrive works and the disk drive works. I took the system board out and tested the on-off switch with a multimeter. It seems to be working fine. I'm at a loss as to what to do now. If anyone knows what I can do to fix this I would greatly appreciate. I think I may need a new system board. If anyone knows where I can purchase a used one or an upgrade and it not cost to much please let me know that too. Thanks a lot!

Steve

[Banti]

Have you anyway of testing the BIOS chip or the built in RAM? If either one of these is out it might (in a rare case) cause the problem you describe.

Sorry I cannot offer more help.

[Swat5444]

There is a reserve battery inside the laptop and I assume that it is a cmos battery and it is working fine. I can't even see where the bios might be on the motherboard. I don't know how to do anything with bios on a laptop.