I'm using GTX 570 single card, also have intel SSD330 hard drive, kingston hyper x blue 4x2GB ram working on 1600MHz (Cpu supporting only 1333 max) all working on P7P55D-E motherboard. Using pcie x8 instead of x16 to get better ssd speed. New motherboard will be better for ssd and memory, but then buying new cpu is inevitable.