i restarted my computer after a message told me to after using ''tuneup utilities''. After restarting the first bit with the logo for the motherboard loads (with the press tab or delete for different boot screens) and then when it should go to the windows xp logo and the loading green bar below it doesnt and just goes black and does absolutly nothing at all, ive tried moving parts around and pushing things in and out and everything on the motherboard and even put in my windows xp boot disc and even that dosent let me boot from the cd. what do i do? please help me lol