Star Conflict lags on Mac ATI Cards?

My computer is a late 2011 iMac.
Processor: 3.06 GHz Intel Core i3
Memory: 4 GB 1333 MHz DDR3
Graphics Card: ATI Radeon HD 4670 (256 MB VRAM)
Screen Resolution: 1920 x 1080
All my settings are the lowest and I am running it in 1344 x 756 in a window. It runs fine when the game begins but once I get into dogfights it drops downs to a few fps. Another thing is that the keybindings menu is fragmented. I know my computer isn’t a great computer but my friend with a late 2010 MacBookPro can run this game without any problems. What I am thinking is that the game isn’t optimized for ATI Cards and that’s what cause the lag and the keybindings menu to not work.

 

Thank

 

 

Please make screenshots with FPS marker when FPS downed.

Game logs needed too.

 

I don’t think so. Even the steam min specs say you need at least 512 MB Graphics card. “512 MB, NVidia / AMD Radeon / Intel (HD 3000, HD 4000) with support for Pixel Shader 3.0 (AMD Radeon X1000 not supported)” And you have only 256. Ask your friend how much VRAM he has. I’m currently using AMD Radeon HD 5450 with 512 MB VRAM and I have no problems. I have about 30-40 fps stable. Only FPS drops are in Conquest or Last Man Standing.