Video card overheating, help!

Hello, I have had this computer for a while now which I have modded up a bit. In the past my video card has overheated and rebooted itself in the past for no apparent reason, even sitting on the desktop with no graphical intensity. But recently I have upgraded to a duel core AMD 3.21ghz processor which I installed myself. (there were no problems with the last one, except I needed something faster) But anyhow this is when the problem started coming up. The video card(Radeon x1950pro PCI-Express) has been over heating during any graphic intensive game or even some test simulations with some freeware analyzers after only a few minutes! The card will rocket from a 60ºC idle to a 105ºC then reboot itself. I am using a 400W, V5+ power supply.
When I installed the processor I just took out the old one and stuck in the new one(it was just a speed upgrade, same duel core AMD processor) and I did NOT add in any drivers or bios changes.. I don't know how to do bios and it seemed to work so I didn't mess with it. Also the processor is running at a steady 59ºC.

-First off, I have checked the CPU, graphic card, box fans and they are running at 100% speed.
-I have tried just sticking a massive floor fan up next to my computer and cranking it on high.. ghetto, but no change.
-Checked all video card and processor wiring, its right.
-Cleaned off card, checked capacitors.

For what its worth I am decent at working with the internals of a computer, but I'm by far not perfect, although I'm sure I didn't do anything wrong on the processor installation.

Should I just say screw it and get a new video card? New video card fan? ..processor? Thanks and let me know of any other info you would need.