Server for gaming

Welcome to Tom's Forum! :)

Work yes, work well no. The CPU's aren't that strong e.g. Opteron 4184 -> http://www.cpubenchmark.net/high_end_cpus.html

PassMark CPU:
$640 ($320*2) Opteron 4184 = 5,105
$320 Intel Core i7-2600K = 10,038

In addition, most games ignore >4 cores of the CPU's, and for RAM 8GB is about the most with any gaming benefit.

Right now cost to performance either the Sandy Bridge i5-2500K or i7-2600K are your bst choices. IMO the i5-2500K with the savings of $100 going for a better GPU is the best option for most folks.