(Credit for revision/changes goes to Nastyhabits....Thanks Gary!) You can only fold on ATI 3xxx, 4xxx, and 5xxx and these instructions apply to only those cards. If you have previously attempted to run GPU2 with no success, uninstall/delete all previous installations. 1)Download and install the client from the link(s) below. XP GPU2 Console Client VISTA/Win7 GPU2 Console Client 2)Create a shortcut for the executable to add to your desktop. The shortcut is necessary for flag placement in the target field. 3)(This step applies to only 5xxx cards) Edit the shortcut properties and add to the existing target exactly as shown, -gpu 0 -forcegpu ati_r700 . There should be a space in-between the existing target and the argument(flags) that you are adding. Reference screen shot below. 4)Set up the clients with the following parameters in the screen shot below(enter your user name, of course). Just hit return(default) for the last 2 parameters. Client will download the latest core and you will be folding if your GPU is stable. Use Fahmon or FHM.net to track your progress. 5) Environmental variables: Add these environment variables. They will minimize your CPU usage. BROOK_YIELD 2 CAL_NO_FLUSH 1 CAL_PRE_FLUSH 1 FLUSH_INTERVAL 128 FLUSH_INTERVAL can be set anywhere from 128 to 256. Lower number for stability, higher for greater PPD output. Forum members have had success with settings betweeen 128 and 200. Please post in this thread if still experiencing issues. Good Luck and Good Folding!