Help, all the latest drivers ATI drivers 11.10 v2., tried a lot of ways, but that does not help. My System Sapphire RADEON HD 6570, Intel Core 2 Duo E4500, ASUS P5K, Intel P35 (Bearlake-P) + ICH9. Thanks in advance and sorry for my bad english!

Check this out:

http://www.gamesas.com/index.php?/topic/1239628-ati-hd-xxxx-and-dualcore-cpu-problem-solved/

You have to create a custom configuration file and apply Steam launch parameters.