iMac Freaking Me Out!

[Kaos Theory]

I own the Mac version of Call of Duty 2, and my nVidia 24" iMac has been behaving very strangely whenever I play the game; every time I turn on the High Quality Rendering option, the game menu screen goes black, but then displays the high-quality graphics if I return to my current game. Could this be an implementation problem with the nVidia 8800GS? Also, I only get about 20 FPS regardless of settings. Shouldn't I be getting more? I am running the game at 1600x1200 res. with high textures, but still...
Also, I noticed that during gaming, my iMac's fan never comes on, even if the computer is running extremely hot to the touch. The only time I ever heard the fan come on was during a hardware scan. Any help would be much appreciated, as I have posted before and never received any replies. Thanks!

Here are my 24" iMac's specs: 2.8 GHz Intel Core 2 Duo, 2 GB RAM, 320 GB HD, 512 MB nVidia 8800GS.

 

[Consultant]

Did you install bootcamp drivers? Is it 2.1?

Did you go nvidia.com for latest drivers?

 

[Kaos Theory]

Not Using Bootcamp

I am playing the ported version of COD2. I bought a Mac so I wouldn't have to deal with Windows. I know that Mac ports of PC games don't run as well as their counterparts, but this seems to be pushing it. Any suggestions?

 

[Jethryn Freyman]

It should run fine with the resolution a bit lower and detail settings on medium. It ran fine on my iMac with the Radeon X1600.

 

[Kaos Theory]

Thanks for The Help

I read a post of a guy that ran COD4 (Mac version) on his Mac Pro at High-Res and still got 75-85 FPS. He had an 8800GT, which is almost identical to my card. I guess that COD4 is just optimized to run with newer hardware and COD2 isn't. Oh well. I wish that more Mac games were developed on Mac. X-Plane 9 was, and it has the single most impressive design I have ever seen; everything works exactly the way it should. It even lets me choose any res I want and add up to 32x AA. I can even put a 500 MB load on my GPU and still get around 60 FPS. Now that's what a Mac can do with the right software.