use fraps and play a game...it show you your fps in one of the corners of the screen as you play. it going to be up to your os..your drives and the ram you have and your cpu and it speed that will limit your fps. with any new builds you want to run some gpu speed test and see if the rig fall withing the rang of others.
fraps isnt a good tool to find fps, use a different tool as fraps also puts a partial load on the cpu. better off using like msi afterburners onscreen fps counter or gameboosters counter, as the programs are lighter.