Only at high resolutions. Newer games should play smoothly at 720p on the 21.5 while older games should be able to play at full 1080p.
One question, don't console games runs at 720p and are capped at 30 FPS (by the way, what is the exact resolution of 720p e.g., 1000 x 300, etc.)? I'm totally fine with 720p for gaming, but would one notice a drastic decrease in visual quality by lowering the resolution? I used to game only on a PS3, but sold it, in favor of just gaming solely on the iMac for the occasional stint of gaming. Would the iMac's 650M run PC games better than their console counterparts? It seems to me that the 650M might even be able to handle newer games at 768p fluidly.
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im getting the 640M because i dont have all the money in the world
You can get the higher-end 21.5" with the 650M for $1399, with the educational discount. Not a bad price at all, and shouldn't break the bank.
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I mentioned this before though 512 MB of the 650M is in the non-retina MBP and the iMac is $300 less. I say go for it.
What is the impact of extra VRAM on gaming performance (e.g., 512MB vs. 1GB)? Does it equate to extra FPS and faster loading of details, textures, etc.?
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As far as I can tell it should be possible... The 660m's memory is clocked at 2000MHz while the 650m is clocked at 900MHz. But how is the 650m still superior to the 640m overclocked? Their the same chip as far as I can tell, just slower clock speeds.
Because a base 650M is superior to a base 640M. In theory, an over clocked 650M will still be superior to an over clocked 640M. The 640M scores below the 10,000 mark on the 3D vantage benchmark, while the 650M scores a little above 10,000. Also, the 650M has a graphics clock of 900 MHz, while the 660M has a clock of 835 MHz. Technically speaking, the 650M should be able to achieve 660M performance with some tweaking-this isn't possible with the 640M.