im looking at getting a new 24" iMac to replace a 17" G5 iMac, i want to use it for a bit of windows gaming aswell to replace my normal windows desktop but dont know much about mac GPUs, i was looking at the GT 130 or the 4850, but some reviews say that the 4850 is slower than the 130, and others say its faster. games ill be playing include UT3, COD4, WOW, and Left 4 Dead