Quote from WinstonTJ:
Dell stopped supporting the Xeon W5580 CPU in the T5500 and the T7500 - I think the difference is 45nm tech vs. 32nm tech and that the new chip is a 6-core. The X5680 CPU is bigger, better, faster - and runs cooler.
The T5500/T7500 is an awesome platform for a desktop but to be honest these CPUs are overkill. I can't run the W5580's at 100% for more than an hour or so or else it'll start to overheat. The X5680 is better - I can run that for hours - but the temps get pretty hot and the fans sound like a jet engine.
These CPUs would be much better off in a server environment with climate control IMHO. Still cool to have and run simulations, etc. on - but wayyyy over kill because you can't use the full capacity of the machine at normal room temperature without worrying about heat issues. Also, there are only 9 memory DIMMS and you really need more than 9GB of RAM in them so things get expensive. Especially the 6-core CPUs need 18GB RAM... IMHO of course.