Fallout 4: PC graphics performance benchmark review - Frametime and latency performance

Frametime and latency performance

With a benchmark technology called FCAT on the following two pages, we will look into Frame Experience Analysis. Basically with the charts shown we are trying to show you graphics anomalies like stutters and glitches in a plotted chart. Lately there has been a new measurement introduced, latency measurements. Basically it is the opposite of FPS.

• FPS mostly measures performance, the number of frames rendered per passing second.
• Frametime AKA Frame Experience recordings mostly measures and exposes anomalies - here we look at how long it takes to render one frame. Measure that chronologically and you can see anomalies like peaks and dips in a plotted chart, indicating something could be off. 

We have a detailed article (read here) on the new FCAT methodology used, and it also explains why we do not use FRAPS anymore. Frametime - Basically the time it takes to render one frame can be monitored and tagged with a number, this is latency. One frame can take say 17 ms. Higher latency can indicate a slow framerate, and weird latency spikes indicate a stutter, jitter, twitches; basically anomalies that are visible on your monitor.

What Do These Measurements Show?

Basically, what these measurements show are anomalies like small glitches and stutters that you can sometimes (and please do read that well, sometimes) see on screen. Below I'd like to run through a couple of titles with you. Bear in mind that Average FPS matters more than frametime measurements. 

Frame Pacing / Frametime - Single GPU

Above a plotted frame-time results of the test run @ 2560x1440 performed with a single Radeon R9 390X (8GB) in 2560x1440. There are stutters with the card at WHQD, I cannot visually see these myself as they are like 1 to 2 ms each. AMD will need to issue a new driver alright. Perhaps tweaking with the game.ini and disabling some Gameworks things might help as well. Overal, for eyes visually things are fine though, just keep shadows at high as well as godrays. 

Above a GeForce GTX 980 Ti in green at 2560x1440. This test run lasts roughly 30 seconds. Overall this is very smooth aside from one small framedrop. 

And now we combine the results. performance wise the AMD card definitely is not doing bad at all. The micro latency stutters however do worry me a bit, but again .. it's not visible to the eyes.