We've been eagerly awaiting the release of Asus' MG279Q, a FreeSync display with an IPS panel and a fast 144Hz peak refresh rate. It appears that the MG279Q may not be able to refresh at top speed in FreeSync mode, however. A poster on the SweClockers forums received their MG279Q a couple days back, and they discovered that the display will only enter FreeSync mode with the system set to refresh rates between 35Hz and 90Hz.
Forum posts might not be the most credible source, but there's official confirmation of this limitation, too. The 35Hz-90Hz range is repeated in Asus' own FreeSync FAQ, which uses the MG279Q as an example of the technology. The page simply says that "FreeSync only can be activated within 35Hz ~ 90Hz."
A lower peak refresh rate for FreeSync probably isn't the end of the world for the MG279Q, but it's a little disappointing given the display's unqualified 144Hz billing thus far. We've requested comment from Asus, and we'll update this post if we receive one.