No, Radeon RX Vega Is Not Running DXR With Battlefield V
Yesterday a very interesting proposition was presented to me by Videocards on twitter. A link was shared with me showing how a user claimed that they believe they had DXR functioning on a Radeon RX Vega. The images on twitter while using my phone seemed convincing enough, but just like when we were tipped off regarding GeForce being able to be tricked into running variable refresh rate on a Freesync monitor I had to absolutely test this when I was able to, so of course I did. After all, I wasn't going to just rush over here and slap together an article talking about how awesome this was if I couldn't get it working myself. The steps laid out by a Guru3d Forum user were pretty simple, navigate to the PROFSAVE_profile under the Battlefield V documents folder and change a few settings
— VideoCardz.com (@VideoCardz) November 16, 2018
So we went straight into it and found something very interesting. Perhaps it's from our previous run with the RTX cards having been saved in the profile .ini, but we already had these settings in the fashion that were laid out in the steps the user provided. So, did it work? I think the title of the article makes it pretty clear, even after setting windows to developer mode in hopes that maybe it was blocking it similar to our early simple ray tracing testing but no, nothing. I even made the .ini file 'read only' in hopes that maybe something was tweaking it after the game launched. I did take some screenshots with default settings and the suggested .ini settings to see if there is a noticeable difference as well as including some like for like shots with DXR enabled on a RTX 2080ti to show the visual differences of the Screen Space Reflections Battlefield V is using.
In the above images you're going to have to compare the reflections of the truck and the trees more centered to really highlight the differences.
In the above images, ignore the gentleman that would simply not move out the way, you can really see that DXR doesn't inherently make surfaces more 'shiny' but rather reflects light as it naturally would through variations in the surface, notice how in the Radeon images all water surface is reflective but in the RTX imgae the reflective quality degrades as it gets to the more shallow areas. You can also notice that DXR isn't kicking in in the Radeon images because of the truck opposing the one directly in front me (the one just past the body on the ground) only shows reflections for the area not being blocked while the full reflection is show on the RTX image. I can however notice an improvement in the Suggested Settings for 'enabling DXR on Radeon' so that's a win, you can see in the images the artifacts around the leaves is much improved so that's a win.
It's really not that surprising that it DXR isn't functioning on the RX Vega card, after all AMD's David Wang already said they won't implement DirectX Ray Tracing (DXR) in games until it's offered on all their gaming product ranges. And support from drivers would definitely be needed as it's not quite as simple as off/on in a .ini file. I had actually gotten really excited at the prospect of this working, I mean why wouldn't you want to see just how something else other than RTX cards could handle RTRT in gaming. But, at the end of the day it does go to show just how good of a job of faking reflections with Screen Space Reflections developers have become, Ray Tracing is the path it looks like we're going down but it's not quite there for everyone yet, just those on the bleeding edge.