FCAT Frame Experience Analysis Tomb Raider
With a new benchmark technology called FCAT on the following three 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.
Frame time in milliseconds |
FPS |
8.3 | 120 |
15 | 66 |
20 | 50 |
25 | 40 |
30 | 33 |
50 | 20 |
70 | 14 |
We have a detailed article (read here) on the new FCAT methodology used, and it also explains whay 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 17ms. 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 ?
But 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 like to run through a couple of titles with you. Mind you that Average FPS matters more then frametime measurements. It's just an additional page or two of information that from now on we'll be serving you.
Tomb Raider Frame Experience Analysis
Above a percentile chart of the 30 seconds @ 2560x1440. Here we plot FPS and place it in relation to percentiles. If you look at the left beginning of the chart, we start at 100% at roughy 31 FPS. Shifting over, 50% of the time measured frames is doing 29 FPS. At the other side of the scope to the right you'll notice that the last 5% of the frames is at 24 FPS or lower. This is another and valid way of looking at performance.
For comparative reasons and a little extra scaling in the charts we included the Radeon HD 7870 With Tahaiti LE GPU from Club3D.
Above the card at 2560x1440. You'll notice that here frametime scaling (chart wise) still needs to be altered, the charts are incredibly blown up, but on this 30 Second run the graphics card manages to remain roughly below 40ms, as you can see there are three stutters recorded, these are actually visible when we recorded this. Not enough to be annoying though. For those that do not understand what you are looking at, the above is a scene rendered. The plot is averaging roughly 35ms to roughly 40ms per rendered frame.
With this chart, lower = better. Huge spikes above 40-50ms can be considered a problem or indicate a low framerate (look at the table at the top of this screen).