I have a similair issue with mine. I can get to use it sometimes at one point it went for an hour but then after it glitched and lost network connection it went 5 minutes the next time.
Basically I found it can run AC 866.7 like person posted above. However it's stability seems to be lacking. I have to disable/ reenable or else it gets in a sort of restart loop with the driver it seems. It shows wireless populating in the scan list and then blanks them out unless I do it. If it does connect it doesn't have internet. I tried just 2.4 or just 5ghz but same thing happens but I know wireless is stable.