wow that sucks...if resetting the bios dont work, switch the ram around, do a bare boot(no cd, hdd, just basics, like cpu, one stick of ram, and no video card unless the mobo dosent have onboard)
this is like dejavu to me, and my hp, when it died, i went to a 366celeron system, was too slow, so i put the 1.0ghz p3 in it, and it killed that too. if worst comes to worst, ur lucky that it isnt a newer dell model, and common stuff can fit into it.
gigabyte 939 mobo - 79.99 amd A64 3800+ - 99.99 Patriot 1GB (2*512mb) ddr kit - 99.99 CM 450W ps - 75.99
i would suggest some stuff for a c2d, but i be knowin nuttin about the c2d mobo's