This is probably going to be an affront to your intelligence, but it is worth asking;
Have you got the GPU plugged into the PCI-e x16 slot? The one with the bit of plastic at the end?
Ha no worries, I'm actually pretty new with working on computers. I'm almost 100% positive I have it plugged in. It's a 6 pin directly from the PSU. If it weren't wouldn't I be facing more difficulties than just low FPS? Like I said, I'm pretty new to all of this so it's a legitimate question