Hi All I thought I would post how I did this because I think most of the guides on the web are out of date. First I should point out that I am using Windows 7 and FAHcontrol V7.1.52 with Nvidia 500 series Graphics cards. I already had one GPU folding before adding the second. 1. Pause folding client then shut down PC. 2. Switch off power then install second graphics card. 3. Switch on power and start PC. In my case Windows detected the new card and installed the drivers automatically. 4. Open Nvidia control panel and check that it shows 2 cards detected. Go to 3D settings / set SLI and PhysX configuration, and check that the Disable SLI button is selected. In my case this also happened automatically. 5. Open FAHcontrol and select Expert mode. Click on Configure and select Slots tab. At the bottom click Add. This gives you the configure folding slots window, just select GPU and click OK. Now the client should configure the new slot and download a work unit automatically. There is no need to plug a monitor into the new card or alter any windows display settings. This was one of the easiest mods i`ve ever done I used two identical cards but this should work with two cards from the same series eg. both 500 series. It will probably work with two cards of the same architecture eg. 400 and 500 series are both Fermi cards. I would not try to mix cards with different architecture. If anyone has information on this then please post. Fold on
