You can't check this for sure, only when it is connected. In my case, it was the Apple TV 4k that didn't work properly at first, despite the supposed 27Gbit/s cable and "Lifetime" cable. But that's not the case. In the meantime I have a cheap Club 3D cable 3m 4k HDR 60fps cable ( Club 3D HDMI 2.0 High Speed 4K60Hz UHD (3m, Premium, Black) ) which only supports 16 Gbit/s, but it works. Save your money for a monster cable.

Hi
For me, the cable (5m) "only" managed 4K 30fps and without HDR. For 4k HDR 60fps, the cable must not be longer than 3m.