why does my pc keep restarting

[brute]

my computer keeps restarting and turning it self off sometimes when i am on the internet it disconnects fromthe internet i have 82% free space left i have tried deleting files and programs too does anyone have any idea how it can be fixed thanks

[vehelpfulguy]

This can sometimes happen if it is is too hot.

Has the PC system unit got plenty of space around it.

Have you taken the cover off to see if the fans or heat sinks are blocked with dust.

If the fans or heat sinks are blocked with dust components get too hot and the PC can turn itself off.

Try blowing out the dust with a hair drier. Best to do this outside.

Try loosening the dust around the fans (carefully) and blowing them out.

[rosedale]

Yep, it's usually one of two things; heat or dodgy memory.

If the suggestions for the heat problem don't work try removing and refitting your ram sticks in the case or moving them to different slots or using one at a time if you have more than one fitted.