Originally Posted by BlueSmoke

Right, firstly, what processor are you running? An uprated fan might help. Also, you can buy a case fan that acts as a second cooler and sticks to the side of the case inside. I've personally never used one tho and I very rarely see the blue screen of death.

Do you ever get a blue error screen? Is your copy of windows legit? Do you have anti virus and firewall, plus spyware remover? A nasty trojan could be infecting this new pc just as it did the old one perhaps.

To be honest I would say it's most likely a hardware/windows conflict but I've been wrong many times before

Just out of personal interest, what happened to the old PC cause I'd love to have it if it was gonna be thrown out.

Hope I've helped in some way.