cpu

[billyo]

2 of my old pc's ( optiplex sx280 ) motherboard went out a while back, ( capacitors leaked ) since i am now retired from work i decided to look for something to do and decided to see if i can work on the pc's,i just ordered 2 motherboards..and also this is my way of learning how to build my own computer.and to keep me busy...the problem now is i kinda mixed the cpu's when i was putting the stuff away.. in other words i don't know which one goes to which now..i'm in the process of getting new cpu's..my question is since i'll be getting new motherboards does it matter what cpu goes to either pc's..my old cpu's were intel Pentum 4 with 800mhz fsb, hyper threading 1mb l2 cache or celeron d processor with 533mhz fsb 256k l2 cache..or can i just get any type of cpu and what will happened if i installed a wrong cpu..running wxp..any suggestions would be greatly appreciated..