Radeon RX Vega 64 frame time & pacing analysis with FCAT

Radeon RX Vega 64 has recently been released, in this review we will be analyzing frame time/pacing in combination with FCAT comparing Vega 64 towards the GeForce GTX 1080. With FCAT (Frame Capture Analysis Tool) we can detect and visualize if there are any problems related to rendering content in terms of stuttering or oddities.

For this article we'll testDirectX 11 and DirectX 12 games. To analyse frametime experiences we revert to our FCAT measuring setup, which we'll explain that technology in the next few pages. This technique allows us to record each frame rendered precisely up to the millisecond. The beauty of this technique is that it measures at the monitor output side, that means everything you can observe with your eyes (or not) is measured. The focus for this article today is the Radeon RX Vega 64, as the GTX 1080 already has had an FCAT review. For the FCAT we rely on DVI output, the reference Radeon RX Vega 56/64 cards do not have one. We just received an AIB RX Vega 64 (ASUS STRIX) that has one, hence we dived straight into the results:

Before you read on-wards, a stutter here and there in any game is common, that is nothing out of the ordinary or weird. It can be something in your system going on, a little mistake in the rendering engine, a shader doing a complex workload, on and on. Stutters and an occasional frame drop are common, big anomalies however are not. Now, considering the things we need to do and invest in, to hunt down anomalies takes a bit of a scientific approach. As such, this article is not for everybody as it is a bit more complex and academic opposed to what you are used to. Since our reference articles are 30 pages long these days, we decided to mostly separate FCAT frametime and pacing results from the reference reviews. Also this is not everybody's cup of tea alright, hence separated content makes a bit more sense. But I wanted to show what we are doing and how we are doing it as transparently as can be. Now then, our FCAT solution requires multiple thousands EUR worth of hardware and is not something you can easily recreate at home. I also left a lot out in terms of complex issues and will take a very simple to understand approach, which hopefully, the majority of you guys and girls can understand.

First let's discuss a little about frametime recording, the method we use (FCAT) and challenges ahead.





The FCAPS setup - two dedicated PCs and two monitors merely for a handful of plotted graphs