I've got a 256mb 9600, and find it fine with the only thing that i do that pushes the video card which is gaming. This is my first mac so i cant compare it with the older one, but in vista x86 and 3dmark 06 ive gotten 6700ish with some messing around. Doesnt mean jack, but i can play crysis at 1280x800 with everything high except shaders on medium and get 30fps in the timedemo. I've done a few benchmarks and recorded temps with a bunch of different drivers, and different settings, clock speeds etc with them if anyone is interested.... Havent had it drop to unacceptable framerates in combat or anything, so its playable like that. The 512mb card id imagine would be faster, but im not dissapointed in mine. You'll have to excuse my ignorance here, but what do you do with a notebook that you need 512mb over 256, and why do you have a notebook if thats the case? I only picked mine up a month ago and are suprised that it does as much as this does to be honest. And i was an annoying pc fanboy before hehe.