A friend's old gateway's hard drive went out on them. It's a old 1.7Ghz p4. Stock except for some added ram. I got a new hard drive and installed it. Put on XP and everything was working fine. Installed SP2 and it starts to boot, windows loading screen comes up and then the screen flashes and gets real small and then it reboots. Goes to the windows didn't shut down properly screen. It will boot into safe mode and let me uninstall SP2 and then everything works fine. Any ideas?