My PC keeps turning itself off and restarting. It seems to do it when its been on a while or when I am multitasking. Maybe the CPU is faulty and getting too hot. All fans are ok and vents vclear. How do I find out what exactly is at fault?
While removing the sides may help it will also reduce the efficiency of your fans. The sides are required to be on so that the fans can draw air over your motherboard and components.
I would agree this seems like an overheating problem. keep the temp monitor on for a while and check or variations on temp, cpu is not the only thing that can overheat. The hd and motherboard are also prone to this.