what you need to do m8 to make sure the m board is ok. is take the cpu out and power up.
if the pc powers then its cpu.
if the pc dose not then its m board or power supply. it can still be shaged if the fans come on .
go to scan,com or co.uk and make ya own for about half that price m8 300-400
then the bits you have on the other one will save you some more cash .
hdd will be ok if the mboard is ok more saved g card ok sound card ok all can be used from theold one .
all in all you can save lots m8 cpu if dead 3.5ghz amd 85.00 plus post