The game is made for consoles. It will run good on them.
When did I quote you saying it's horribly optimized? I did not. But it is.
I have a core i5 system and I get 25FPS, and yes, I have hyperthreading. All I'm saying is that don't expect too smooth gameplay on the 610 - it's a bad card for gaming. Very bad.
Disregard the system requirements. The game needs WAY more than those.
Where am I getting my statements from? Search the net. Or these forums.. there are quite a few threads related to GTAIV.