I also installed Windows XP RC1 numerous times, with it I installed the following programs: Office XP, NAV2K1, Zone Alarm Pro 2.6.84, & AdSubtract Pro 2.11, now my problem, it reboots itself suddenly, with no warning, and no set time limit (ie. every 6hrs.. its sudden) and does it very often, does anyone know what may be causing this? any help would be appreciated. Thanks.