What about multi-gpu support and the -gpu switch?
Running multiple GPU2 clients, one client each on multiple GPU cards, is supported through the -gpu x command line switch. The setup is similar to running multiple SysTray CPU clients.
* Copy your \Application Data\Folding@home-gpu folder to a new folder \Folding@home-gpu2 (\AppData\Roaming\Folding@home-gpu in Vista)
* Create a new shortcut for the first client, and be sure to use the correct Target: and Start In: information. Note that one has to be very careful with shortcuts, and in particular, make sure that the "Start in:" field is set correctly. If you are having problems with automatic core upgrades, it is likely that your short cut is not set up correctly.
* Edit the shortcut properties to add the -gpu 0 switch to the end of the Target: field.
* Create a new shortcut for the second client, and be sure to use the correct Target: and Start In: information.
* Edit the shortcut properties to add the -gpu 1 switch to the end of the Target: field.
Except for the different -gpu x switch, the Target: field in both shortcuts will point to the same FAH executable. The Start In: field for each client will point to the two different \Apps Data\FAH folders. The Target: and Start In: fields for a SysTray client are explained in more detail below.
The display must be active on the GPU card you plan to use, and ?gpu 0 will select the first board, ?gpu 1 will select the second board, -gpu 2 the third board, and so-on. You will need to disable crossfire for multiple boards to be detected. You will also need to use different Machine IDs for each client. Currently, only one client is supported on a 3850X2 or 3870X2.