FPS question

I have been having issue lately with foreground/background FPS limits now I have all my screens set to 60 foreground and 30 limit.


However when I bring a new window to Foreground it stays at it's normal background FPS usually 15 not sure why it's 15 I play another 5 guys and they switch fine and stay at 30 a piece. The only thing different is now I am playing 4 dk's 1 holy paladin instead of healer/tank/3 dps. Could it have anything to do with that all my characters have the same cpu setup, and windows. I am currently using hyperthreading with round robin with dedicated cpu 1.

My apologies I looked into it and it just seems to be hardware related somewhat, not sure why my slaves aren't going to 60 fps but my low all around fps is due to being on High pop server.