2GB are not enough when using very high MSAA:
Everything else maxed out:
No MSAA = 965MB
2x MSAA = 1117MB
4x MSAA = 1421MB
8x MSAA = 2030MB
Then again even if you have 3GB vram I don't think any single gpu card is fast enough for 8x MSAA. My 7970 averages 25-30fps when all is maxed out, which while playable is not very enjoyable. With 4x MSAA it drops to 40fps in some scenes and stays around 60.
Also some guy at Hardforum wrote that MSAA is uglier than FXAA in Max Payne 3 and provided screenshots. I tested myself and came with the same results:
8x MSAA + Very High FXAA:
2x MSAA + Very High FXAA:
8x MSAA + No FXAA:
Very High FXAA Only:
I would have to say FXAA only looks the best and for some weird reason MSAA does the opposite of what it should do: you can clearly see the jagged edges on the white sofa and at the wall on the left.
That's with Gigabyte 7970 OC Windforce