I have been considering modding my Xbox 360 more than it is already. I bought it on ebay about three months ago, but only opened it two weeks ago to mod the DVD drive firmware. I discovered that the heatsink has been replaced with a larger, probably more effective one. The GPU chip has an extended part like the one in this picture:
I had been considering cutting up the top and putting a massive case fan on the top of the extended GPU heatsink and the cpu.
Also I am buying a motherboard today. This motherboard to be exact. I believe that it is compatible, although if anyone wants to back me up on that it would be nice. I have an Athlon 64 X2 3800+ that is socket AM2.

I wouldn’t expect it to work completely flawlessly, but it is compatible and should work.
Perfect!
That motherboard for your XBOX?
No, It is for McCall’s computer that I am building. My Xbox has a Jasper series motherboard with HDMI.