Review on ASUS PG329Q: 2560X1440P DisplayPort DisplayHDR, 175Hz Refresh Rate, Flicker-Free & Adjustable - A Comprehensive Review by Dante Kohl

So this monitor is great until it dims. During use, it will automatically dim at random intervals. This is a known issue. As detailed on the Linus Tech Tips forums and in several posts on the Asus forums. What happens is that the monitor automatically dims very dark when used at random times. What Asus support told us was that this is a "feature" that preserves the matrix. Essentially a refusal to acknowledge a problem or provide a solution to it. Also, it's DP 1.2. So yes, even though it advertises 175Hz, there's an awkward flicker above 144Hz because the DP can't support 1.2 bandwidth, which is what it takes to hit 175Hz at 1440p flawlessly. I returned this monitor and chose the Acer Predator xb323u. It's the same panel (basically the same monitor), no problem, and DP 1.4 eliminates flickering.