The input lag on this display is typically around 50-70ms. This is unusually high, and with a PC connected, you can feel the drop in speed as you drag a window around on the TV screen.
However, this can be improved a little, with some conditions. In the TV’s [Input] menu, labelling the HDMI input as “PC” (using the [Edit Name] function) will disable certain picture processing circuits and drop the level of lag to a more tolerable 30-40ms. As a result of bypassing certain circuits, some options in the Picture menu will be greyed out. Sadly, one of these is the [Smart LED] option, which is, presumably, a major selling point of this display since it holds the keys to the regional dimming option. And, the level of lag is still higher than several other displays on the market.
Additionally, there’s an [Entertainment Mode] setting called “Game” which also drop the level of lag to around 30ms, but as this forces unrealistically high brightness and sharpness settings (amongst others) on the viewer with no chance to alter them, it is effectively useless.