He shouldn't really. Some one gave numbers for G620: the CPU usage was at 100% constantly, but he would get stable 45-55 fps at 64 player maps.
I struggled with a Q9550 (w/6GB ram) until I shut down all extraneous processes, it was little stutters and stalls, but only only on 64player tdm, this was with a GTX470, it went away when i upgraded to a 3570k through sysprep so the software was all the same. On smaller maps or less densely populated maps there was no problem. CPU usage was 95-100%.
from an FPS standpoint I was getting either 55-60 (med ish settings) or 0 for short periods of time.