Which ATI driver version is installed?
Have you tried older or newer versions?
Is your cpu and/or memory overclocked? If yes, what settings are your using?
Is your video card overclocked? If yes, what settings are your using?
What is the model name of your OCZ ssd? How much free space does it currently have?
What screen resolution are you using? 1920 x 1080?
What are the specific game settings (e.g. quality/performance) that you have set in your games?
It sounds like you are "pushing" your video card to hard.
Have you tried lowering the settings in your game(s) to see if your graphics drivers are more stable?