Problems booting...

[corksil]

Hello all, I'm fixing a computer for a friend, and he is having problems booting. Every now and again when he boots up his laptop, after the 'Compaq' screen loads, during the loading of Windows XP (When the loading bar is going and the logo is displayed.) The computer goes to a black screen without a mouse, and sits for about 5 minutes before entering Windows. He was having this problem some time ago, and we formatted the drive and re-loaded Windows. For about a month, the problem was fixed, but now the computer is starting to do it again, leading me to think that it may be hardware related. Thank you for help in advance.