I'm somewhat new to Linux. I've dabbled with it before but never more than just experimentation in a VM or dual boot where I almost always reverted back to Windows soon after (more due to a lack of commitment than a dislike for the OS).

Anyway my problem is that in the two games (Guild Wars and Team Fortress 2) I've tried so far I get fairly bad performance. Despite both games having a "Platinum" rating I've still been forced to run both in DirectX 8, otherwise they either crash, have texture defects or the UI is missing. By "bad performance" I mean sub-30 FPS where there are some players and regular large framerate drops with video settings on low.

Currently in my mind I believe the performance issues are just a problem with the drivers because my graphics card is a AMD 7850 which is virtually brand new and probably not properly supported yet but I'm unsure and would appreciate advice or tips to improve things.

I have Ubuntu 12.04 installed and I am usually logged in a Gnome Classic session. I have installed AMD's proprietary drivers (Catalyst version 12.4) and have Wine 1.4 installed. I have used Winetricks to install DX9/DX10 dlls and other things.