BenQ is adding to the growing mix of 4K monitors supporting HDR with its new EL2870U, a 28-inch display "designed specifically for home entertainment." That includes gaming, even though BenQ isn't billing this as solely a gaming display.
Let's start with the HDR claim. The field of 4K monitors with HDR support is expanding, though still far outnumbered by 4K monitors without HDR. In this case, BenQ advertises HDR10 support and includes a premium high-speed HDMI cable that it recommends using for HDR content.
That said, the brightness is rated at only 300 nits (cd/m2). At that level, it doesn't qualify for VESA's entry-level DisplayHDR 400 certification, which among other things requires a brightness level of at least 400 nits. Ideally, a true HDR display would be capable of 1,000 nits or higher. However, BenQ is far from alone in pushing HDR on displays with much lower max brightness levels.
The EL2870U uses a TN panel with a fast 1ms response time for fast-action gameplay. It also supports FreeSync to smooth out the visuals if you're running a Radeon graphics card. Or you can read that as "not G-Sync" if you own a graphics card from Nvidia.
There's a pair of built-in 2W speakers on this monitor, though no USB hub. Connectivity options consist of DisplayPort 1.4 and HDMI 2.0, and a 3.5mm audio port.
BenQ lists this monitor for $499 on its website.