i just took this compaq presario 2100 laptop apart. i was going to put a 2.4ghz P4 in to replace the celeron 1.8. turns out the celeron has no IHS and the p4 does so it wouldnt fit. now, when i put the computer back together, it wont boot... at all. wont even power on. can anyone advise me on what could be wrong? i tripple checked everything, and it just wont boot. i really dont want to have to buy another one and then swap the HD's out, but if i must then i will. i need to fix this by sunday. any advice?