Sorry people for the connection in my brain to take so long.
I think I know what most people's problem is, as long as they do not have a junk processor like AMD's FX-4100.
Are you, who have terrible frame rates on good machines, on DirecX 11 or DX 12 capable machines, including using Windows 8 or later? I think you would benefit from installing DX 9 and DX 10.1 next to DX 12 (or 11 if you are still on that). You would think DX 11 and 12 would come with full support for DX 9 but that is not the case. You can have ie DX 12 and DX 10 and DX 9 installed next to each other no problem. Just download from MS or other trustworthy site.
Also, know that you can force use of DX 9 instead of DX 10. I forgot how to but you can search for it yourselves. I had to use that as my DX 10 capable GPU could only serve me a slide show ten years ago.