What type of hardware is it? (hp or dell, or custom)
the reason I ask is manufactures have some of the best diags for memory and such for their units for free.
Diag 4.6 is pretty decent (you can run in windows, but you output is off, copy to a floppy and boot to floppy)
Free
http://www.brothersoft.com/downloads/hardware-diagnostic.html
