Since you do not provide your hardware infos, I can only estimate this : 1- If you have Intel or ATI/AMD graphic card, it's over, Intel cards are not real "3D" cards (from my point of view) and ATI/AMD Linux driver is simply horrible 2- Your configuration simply do not match minimum requirements to ply this game. 3- You did not used lastest wine (unstlable) which is nealy mandatory with Steam (god I hate this crap) and did not followed AppDB test's instructions for this game. If you want an easy way, try PlayOnLinux, Portal 2 is perfectly playable for me with it, solo and co-op. (http://www.playonlinux.com) If you absolutely want to use only wine, follow AppDB entry for this game, all is explained. Good luck 8)
