UrbanaJamie

I have had this problem, too.
I'm running newer i7 processer, Windows 10, and two GTX 980ti.  I've tried all above, but, here are a couple of 'tweaks' that I needed to do on my machine to get FAH to work:
1) make sure to uninstall all previous versions of the FAH client using the Control Panel uninstall.  During uninstall, when prompted, check the 'data' box, too.  I also deleted all previous versions of the FAH install application (file named fah-installer_7.4.4_x86.exe; it was in the 'C:\Users\[userName]\Downloads' folder).
2) I restarted the machine ... just to ensure it's a 'clean' boot.
3) I re-installed the FAH client from http://folding.stanford.edu/
4) At the end of installation, a screen appears that prompts me to push a 'Finish' button - DON'T DO IT! I let the installer hang while I copied the GPUs.txt file into the folder C:\Program Files (x86)\FAHClient (yes, my location was in a different location)
5) then I pushed the 'Finish' button back in the install application window.  The FAH client then recognized all my GPUs.
Good luck!

People have an incredibly short memory. I will upload a bunch of tech stuff, then one video of a battery powered hammock or something and sure as shoot there'll be a thread on the forum "Linus has forgotten his core audience, etc"