Input lag is the delay between the game receiving an input from a peripheral (such as a keyboard, mouse, or gamepad) and the monitor displaying a corresponding action, or in other words the time between when a button is pressed and when you see the action performed in game. In actuality, input lag can have one of two causes. It can either be due to input latency, or a delay in the signal from the input and the receipt of that signal be the I/O port, or it can be output latency, or the delay output registry being set to reflect the change once the signal is received. In short, input latency is a delay in the signal from the input device (controller, keyboard, etc) while output latency is a delay in the signal from the output device (monitor, TV, etc). Over time these two issues have been combined under the blanket term input lag. There are a few possible causes for input lag.
Controller to Console:
For wired controllers this shouldn’t be an issue, but for wireless controllers there can be some very slight input lag. The additional lag should be negligible (4-8 milliseconds), but if there is something interfering with the wireless signal it may result in a higher input lag.
Network Lag (Online Only)
Sometimes in online games, the input signal is held to allow the signals to travel over the network before an output response is sent. This may result in input lag traditionally associated with online gaming. While more common with much older games, newer games have code to compensate for any network lag and allow for smoother gameplay. A particularly weak connection or server issues can result in network lag becoming a bit more noticeable though.
Console/PC Process Next Frame
While the console or PC will send out a new frame once it finishes performing the necessary calculations, the overall frames per second (FPS) can not exceed the refresh rate of the monitor being used for output. The V-Synch option does get around this, while simultaneously causing some artifacting to occur. If you are using an older or outdated monitor, the refresh rate may be the cause of input lag.
You should first test and see if you are experiencing any input lag, as it can be hard to tell by eye. You can use online software or other methods to test the input lag. Most flat screen displays have some kind of latency or lag, so the goal is to get it down to the point where it’s no longer noticeable. Once you’ve determined the latency, here are some additional tips for reducing it:
-Set your TV or monitor to game mode if it has one. This will set it to the optimal settings to reduce input lag.
-Turn off any power saving modes or dimmers.
-If using a TV, test multiple HDMI inputs, some may have less lag than others.
-For TVs, use a separate audio system. The additional processing time for the built in speakers can occasionally add minimal amounts of lag.
-For TVs, if possible label your input as PC. There are often times specific settings that will be applied to reduce input lag.
-If the game has it, configure the latency options to have the game compensate for any remaining latency.
So that’s it! The next time you experience an Input lag or someone asks you what is an input lag, send them to this article.