AMD use to generate more heat ONCE, but they eventually become cooler since AthlonXP, and when Athlon64 series came out, they were with thermal Diode built on chip. so now even if you remove the fan, it will automatically shut down the system to prevent permanent damage.
Intel were giving thermal diode since Pentium-III, but as they moved to 90nm fabrication, there processors started generating more heat than their previous models on same clock, this was against the actual facts as when moving to 90nm, their processors should have ran cooler on same clocks. I read somewhere that they coujldnt control the current leakage within the 90nm DIE. so eventually they cancelled the 4.0GHz P-IV Processor. even you buy Intel's original FAN it will start throttling after prolonged usage on or above 80% of CPU power. result = long term CPU damage.
In Intels, Until Northwood core, CPU's were 100% perfect, problems started arising after that, I had used PIV on orthwood 3.2 with average temp of 44-48 (depnding on AMbient), as when I have recently moced to AthlonX2, it averages to 39-43. C
Intel Core2Quad 2.66Ghz 12MB L2-Cache
4096MB DDR Kingston Hyper-X
XFX 9600GT AlphaDog
Seagate 2 X 320GB SATA2
LG L246WH Flatron 24"