The first computer is three years old, but have replaced parts as needed. Problem started on this computer about two years ago. Replaced MoBo (3 times), video card (first one was a Radeon 9550, second is a Geforce 6200, AMD cpu Sempron 3200+ to a 3300+, 4 power supplies, Replaced HHD's wth 80 gig Seagate had off brand. My Daughter's computer has same MoBo, 1 gig ram, the Radeon 9550, The AMD 3200+ cpu, original PSU, and new HHD's. This computer does not have a random reboot problem, also has Windos XP /SP2. Third computer was just built, got all the parts together within three months and put