My Kingdom for a Computer Tech

Ok, my computer will work for a few minutes, and then abruptly shut off completely, going all black. It won't restart until it cools down. Do I need a new fan perhaps? Or just need some compressed air to blow out the dust? Or a witchdoctor?

Anyhoo, the comics were all and more that I expected. I'm typing in a frantic hurry, to get this on, before it implodes again, so hopefully reviews tomorrow!