System latency is a new addition to our testing, where we use Nvidia’s Latency and Display Analyzer Tool (LDAT) to measure end-to-end system latency. LDAT itself is a photosensor which is placed on the monitor. It has an integrated mouse button, allowing it to measure the total time taken from mouse click, to an action happening on screen, which is done by measuring a change in luminance. This data is logged to a CSV file over USB, allowing for close analysis of the data.
As this is end-to-end system latency, we are not measuring only the processing/input latency of each monitor we test. However, we can standardise the test process so the monitor is the only variable. It also gives an insight into how different refresh rates and resolutions can affect end-to-end latency, which is of course highly relevant to your purchasing decision.
We use Rainbow Six Siege for this testing. The AG493UCX is only the second monitor we have tested with LDAT so we currently have limited data, but we will add to these charts as we review more screens.
While we don't have any ‘like for like' comparisons to use against the AG493UCX, the most interesting thing to draw from this data is how effective the monitor's Low Input Lag setting is. Enabling this results in a 12ms reduction to average latency, so it's definitely worth turning on.