ElvenRecorder, since we last spoke, there were a few updates for my chipset, etc. that magically appeared from Windows update. I have chosen to disable the automatic updating, so I'm now receiving updates manually (similar to how it was with Windows 8.1).
I decided to test my installation again, and for some reason, I was able to get 350+ FPS on 1.7.10. I'm honestly not sure what caused the initial issues, but everything seems good now.
Again, I very much appreciate your taking the time to test this for me. If I have any other issues with my installation, I hope you don't mind if I contact you. Do you support only vanilla, or are you well versed with chocolate as well (I see your comment in your signature, but I wouldn't mind more info from you)?
Oh, and please disregard my last private message as it is no longer relevant. Thanks again, ElvenRecorder!