BadDay

That's weird, I've read that this monitor works only with firmware V2, you might wanna check your version. I got it working @ 140 and 144 hertz too, 144 is a little bugged (only in windows and switching the monitor on and off, very unstable), but 140 is ok. I also got the latest drivers for this monitor, then it showed this 140hz option in BFV.

I have the same monitor and was having the same issues; -set refresh to 120hz -disable blur reduction -using 2 g-sync monitors at the same time is not recommended, if that's the case, disable g-sync for one of them. hope this helps, working really well @ 120hz.