Originally Posted by StratosP
Long story short;
AMD runs hotter but is cheaper.
Intel is more expensive but cooler.
A fictional story.
Both AMD and Intel have processors in the same heat class, and both have processors that run cooler or hotter than a cooperative processor from the other company. It's fairly neck and neck right now.
Historically AMD's have been warmer running than the intel, specifically with the AMD XP days. During the AMD Athlon 64 / late Pentium 4 days, AMD processors ran far far cooler than the Intel counterparts as well as ran faster, and were much cheaper.
Price wise, it's also neck and neck right now. Whatever is the best buy for the money depends on the application and the time, it can shift every few weeks.
Also, right now it appears Intel's architecture is superior, however both AMD and Intel have had major flaws in recent dual or quad core processors (Intel's huge processor security exploit and AMD's virtualisation and timer bug.