How to know the input lag of a monitor ?

[therios]

im considering a monitor for gaming
and it has a va pannel and a 4ms response time but i cant find its input lag in the spec sheet .. if some one can help its called benq gw2470ml

 

[RememberThe5th]

4ms is response time of monitor thats what you're looking at.
Input lag is for example if you wanna to move your mouse and if you move it and on screen the arrow lags behind that is input lag, same goes for key press.

 

[cryoburner]

Input lag generally isn't listed in a display's specs, and even the listed response times can be a bit unreliable, in that there are multiple ways of measuring them, and any testing is done by the company making the screen itself. In general, you'll need to check in-depth reviews to get an idea of what a screen's input lag might be like relative to others, though one site's measurements can't be directly compared against screens reviewed at another site, again due to changes in how it can be measured. And not all screens even get proper reviews that test things like input lag, which seems to be the case with this one.

If you are really concerned about input lag, you might want to look at high refresh rate screens (like 144Hz) since they are generally a bit better about that compared to 60Hz models. They tend to cost upward of $200 though, which is probably a fair amount more than you are seeing this screen for.