Hi, Just curious, if there really a big difference between the Radeon 6750M & 6770M performances in the 21.5" iMacs? Previously I was using the 21.5" i3 iMac, with 256Mb Radeon 4670. Completed Crysis 2 & Portal 2 on Boot Camp. Resolution was decent at medium settings with no lag. AA & AF all turned off. I know that I'm not getting the best resolutions but neither am i getting the worst. In the 1st place, expectations have to be lowered since I was using the lowest-end iMac for gaming. Kinda glad (and lucky i guess) i sold off my 2010 21.5" iMac bout 1 month back. The newly revised specs & pricing are a huge welcome.