How to cap frame rate (or GPU usage) in Just Cause 2 PC?

I play Just Cause 2 PC on my Radeon 4850 (single slot) and no matter how I tweak the graphic settings (from lowest to highest), Afterburner utility keeps telling me that JC2 is using ~99% GPU utilization.

At that level, R4850 temp could hit easily 100C, cranking the fan to maximum speed.

R4850 clock rate is 500/750 when idle and 625/993 when under load. Afterburner lets me cap with 500/750 under load but JC2 hogs the GPU nonetheless.

Can anyone suggest a way to cap my GPU in terms of GPU usage or frame rate?

BTW, I plan to buy a replacement in AMD's Southern Islands (R7XXX series) once it is out.

Solution 1:

Add to the game's command line parameters: /frameratecap=n where n is the frame rate.

Solution 2:

Force VSync on in the Catalyst Control Center, this should cap your frame rate to the refresh rate of your monitor (probably 60 or 75) which will reduce utilisation of your GPU.