[atullio]

why is it that macs cannot run games? i have a 1.5ghz g4 poweboook w/128 and a g5 with the 9800 special, youd think there would be a dramtic difference in performance from our old card, gforce with 64 mb. WHY WHY!!!

[Daddymac]

Which games are you referring to, and what types of problems are you having?
Gaming on a laptop is hit or miss, in my experience...but the G5 should run everything fantastic...

[atullio]

well, mainly halo, and tron 2.0 run chopy as hell. its hard to get halo over 30 fps, epecially above 640x480, i am as baffled as you.

[a2daj]

Both Halo and Tron 2.0 make heavy use of flares when they're enabled. As of 10.3.4 there was still no hardware accelerated OpenGL API available for Mac OS X for programmers to use to make the flares faster. Instead, many games use a function called glReadPixels() to deal with flares and it can cause major slowdowns because of how it works. So right now, no matter what Mac you have, if you have games with lots of flares, they're most likely using glReadPixels(), and thus will perform badly. Often times, the performance hit is even more dramatic with Full Scene Anti Aliasing enabled.
For Halo, you can turn flares down to medium or low and see a noticeable performance boost. The option is in the startup dialog box that many people disable.
In Tron 2.0 there should be an option to turn of flares Options->Performance->Display->something about Screen Glow.
Other games, like the Jedi Knight games can see a performance boost with flares.
With 10.3.5, a feature (ARBocclusionquery) has finally been implemented for any card with hardware TCL which could theoretically help Flares performance a great deal but I don't know how much work the developers would have to go through to implement flares with the new feature. Plus users would have to have 10.3.5 to take advantage of it.