Hi, I have a framerate problem with my game. There wasn't any problem with the framerate on my pc. fps was 60 and game was good running. Even with many objects. Now I tested on a different pc and framerate is down and the game "shakes".
Especially ref is very high. Have anyone an idea why the framerate breaks down?

The pc with the low framerate:
ATI Radeon HD 4300/4500
AMD Athlon 64 x2 DualCore Prozessor 5200+ 2.7 GHz
2 GB MB Ram

the screenshot: