Fusion window is very laggy when dragging around on the desktop

[karelLLHNN]

Just put together my old computer to run fusion as a dedicated machine as i couldn't runt 2 different cards in my main unit. 

its an i7-8700k with 32gb of ram and nvidia rtx a4000

i would hope that it would work well but it doesnt, even dragging the fusion main window around on the desktop is lagging alot. 

any ideas?

[e1]

did you figure out why? mine is really laggy too when dragging it around