FX 6300 @ 4.5 GHz
GTX 770 2GB @ 1250 Mhz
Resolution: 1080p
Adaptive vsync
Environment quality: high
Shadows: low
Textures: high
AA: off
AO: SSAO
The above settings are a compromise between performance and graphics fidelity that I actually notice during gameplay. I average 45 fps running around big crowds and streets. It can dip as low as 30-35 fps in interiors with a lot of details. I get around 55-60 fps on the rooftops.
In 1.2, the game would stutter every 5 seconds but setting the game's priority to normal (default was high) in Task Manager fixed it. The stuttering now seems to be fixed in 1.3; however, the game still crashes occasionally.
1.4 and the supposed performance fixes cannot come soon enough. This is the best AC game I've played and it's a shame these technical issues ruin the experience.
So the above settings were unplayable in the later missions with a lot of interiors. I believe it was a vram issue as turning textures down to low was the only solution. Unfortunately the game looks terrible with low textures.
I'm pretty annoyed that there is no medium texture setting. It's either get a new GPU or enjoy PS2 level graphics