Two 4K monitors were announced by ASUS at the show. Both use VESA Adaptive-Sync for variable refresh rate (VRR) gaming, which means they are compatible with AMD FreeSync, but not NVIDIA G-Sync. If you want to use the latter VRR standard, then you would be more interested in the ROG Swift PG348Q monitor that was announced in September. There was talk that Intel would be implementing a VRR format VESA Adaptive-Sync in a future GPU.
If you're still here, then you either don't care about variable refresh, or you are looking for an AMD-compatible one. The first one is the 24-inch MG24UQ. It is based on an IPS panel, which are used for vibrant, precise colors and wide viewing angles. They tend to be a little slower than traditional “gaming” panels, but that is so low for the last couple of years that IPS is considered a pure upgrade. The second monitor, the 28-inch MG28UQ, is not IPS, though.
Again, no pricing or availability yet as it varies by region.
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