Computer shuts down after 1.5 hrs?

depends which fan - Dells dont always have main fans. Try opening the side casing and letting it run with side off. If still a problem then the psu can give the same symptoms. If you play mainly games then also check the seating of your graphics card. any of these overheating will cause shutdown. Can also be motherboard overheating where cpu is mounted

alan
September 2007