Gameplay very choppy, CPU issue?

[f0xh4x0r]

As soon as I start the game, the program acts very choppy with the graphics. But it isnt a video card issue, its a CPU usage issue, because it chops everything not just the game. Putting the priority higher helps but then I can't really use my PC at all let alone play Fiesta. I have an AMD 3000+ 64-bit at 2.00 Ghz, that should be plenty of power to run this game..

Specs:
AMD 3000+ 64-bit 2.00 Ghz
1GB DDR RAM
DSL connection 5.1/1.2 Mbps throughput
Windows XP SP3 x86 Updated
Nvidia Geforce MX 420, updated drivers

Suggestions? Ive already tried killing as many processes as possible, defragmented HDD, and im about to try installing on a free partition. Searched but it doesnt seem any one else has this issue. Search: choppy


-h4x

[f0xh4x0r]

Strangely enough it was the default windowed mode the game starts out in. I had to create a character and go into the options to change it to full screen. How annoying? Thank you anyways though