I'm running a quad core 2.4 Ghz with 4GB ram and an 8800GTS 512MB video card, using 5 clients with keyclone/maximizer, and the performance is ok everywhere except in Shattrath and Orgrimmar. It slows down my clients to the point where it's almost unplayable... I mean <8 FPS, clients freezing or not responding for 10+ seconds, while I get an easy 50FPS on my main anywhere else. I'm very concerned it's caused by all the otehr players, since my main goal for these guys is to do PvP in AV which will be impossible if it's similar to what I see now in Org/Shatt.

Is this normal? Is anyoneelse having this issue?

I turned all graphics options down to the minimum on my slaves and to medium on my main. Sound is off on all slaves. Slaves are set to max 15 or 20FPS I think.