You will get very low performance out of games, my systems get low performances on games too!
well here is my system, it gets crappy performance, all because of the video card.
P4 2.8ghz 800mhz bus 1mb l2 cache LGA775
1024mb PC-3200 Dual Channel
GIGABYTE 8IPE775-G "Inte 865PE"
128mb Radeon 9600 PRO
40GB 7,200 RPM 8mb Cache HD