Not sure about that setup, I have i7 and from time to time I would run up to 5 clients. I set up effects on low, but resolution is 1280x720 on all of them.
Biggest part of multiple clients (or good run on 1 client) is memory. You have to have enough memory, and install memcleaner program, as ROM by itself is bad with memory management. I rarely have client crash, even when going trough 10 different zones in 48 hours gaming session. ( I don't turn off client, just leave it on over weekend)