I am building an 8 core AMD Opteron 6100 server, and I can't decide if I should use 1333 ram or above with cas 8/9 or 1066 cas 7 or less. Is it better to go with a even mix of both or should I go with one or the other?
More aboutclock speed
You should go with the recommended RAM on your motherboard producer's page. Don't mix the RAM anyway.