FPS are perfect.
You are a lucky guy! I'm awared from the start I'm not...
I know about core limitation, since GPL is a very old program nowadays, so for sure more GHz you have, better you go. Not so sure about the fact it's installed or not: I've runned the sim in other 2 computers in the past, oldest was a PIII 800MHz (2001->2006), then PIV 3,4GHz (2006->2013), both times GPL was installed from original CD, then patched, added tracks, cars, mods, graphic updates, utilities, etc., each time a gfx update for tracks and or cars added, each time less fps I had. On my actual pc was not installed, but worked quite well till last week. A couple of times I've also ported games from my older to newest computer without proper installation and worked as normal.
Just to say, if I remember correctly, when in 2008 Nigel released the rasterizers wrote that in any case GPL use very few processes and resourses from the GPU, due to the primitive graphic engine, so most of the graphics go to the CPU along with physics etc. So I wonder if, at least in my case, AA go to load and slow down the CPU, instead the GPU as normally should be.