Path tracing on the PlayStation 5. As far as we're aware, there's no shipping game or demo on the Sony console to use it, but the recent release of PS5 Linux is a game-changer. Anything that can be done on a Windows PC can now run on the Sony console, so there's nothing to stop users running Quake 2 RTX, Portal RTX or even Cyberpunk 2077 in RT Overdrive mode - and that's exactly what we've done for our lead story in this week's DF Direct Weekly. Perhaps not surprisingly, there are good reasons why path tracing isn't a good fit for the PS5 - but we think there is at least one shipping path tracing game that would benefit from a port to the Sony machine.

First of all, a quick word on PS5 Linux. It's available for consoles running on older firmwares - specifically up to system software 6.02, which was released way back in October 2022. Older firmware revisions have exploits that can be used to bypass PS5 security, which makes running Linux possible. This means that unless you've archived a PS5 console running on an older firmware, you'll need to acquire one - as I did. From there, I simply installed Steam on Linux and downloaded the games I wanted to test, with the Proton compatibility layer taking care of everything else.

In this week's DF Direct, I first tested Quake 2 RTX, then Portal RTX and finally Cyberpunk 2077 but for this purposes of this piece, I'm going to assume you'll want to know how on earth a PS5 can run path traced Cyberpunk at a playable frame-rate. And the answer is simple: by cutting back settings wherever possible, lowering resolution and using upscaling and finally by using path tracing optimisation mods. These two images show the stages and there are some other performance shots following that.

In the first image, we start with a relatively modest target: full RT Overdrive at 1080p output resolution (470p internal!) using XeSS performance mode, where we achieve a 22.6fps average. This is objectively not great but actually better than I expected. I boosted frame-rate by 19 percent by moving to 1920x800 resolution - ultrawide, if you like, which takes our internal XeSS pixel count to 348p. A 26.9fps result is better, but we're going to need much more to deliver a 30fps lock.

Using a path tracing optimisation mod reduces ray bounces from two to one (don't worry: PT still looks good!) and in combination with equivalent rasterisation settings to the Switch 2 version of the game, frame-rates are increased by a further 32 percent. The Cyberpunk 2077 benchmark now runs at a 35.5fps average, and that's where we left it. I also tried FSR 3.1 frame generation which took us up to around 70fps, but the interpolated frames looked poor - presenting as a "wobble" rather than delivering any additional smoothness, so it wasn't a focus moving forward.

Cyberpunk 2077 with path tracing is therefore playable but doesn't particularly look great. We don't have a reasonable denoising solution so the PT effect is grainy, while the base resolution is so, so low and we don't have a decent upscaler. In a desperate attempt to make it look decent, I engaged XeSS ultra quality mode and turned on frame generation - a kind of Lego Batman approach if you will - but while it looked better, it obviously didn't play better.

The only thing we have really learned here is that maybe the PlayStation 5 Professional could pull this off via its more potent GPU and more advanced RT features. While the denoising problem couldn't be addressed, resolution could be higher, while PSSR2 is a much more effective upscaler. Compared to the high resolution outputs of the actual Pro version though, I doubt it's going to be much of a priority for CD Projekt RED.

I wasn't that impressed by running Portal RTX on PS5 either - remember, this was Nvidia's first big project for its RTX Remix path tracing modding system. Here, I could use the low setting in combination with a 1080p output, upscaled from 540p with TAAU. Performance ranged from the mid-20s to the mid-30s in the first bunch of levels, but really the core problem beyond the frame-rate reading under 30fps comes down to the same issues with Cyberpunk 2077 - the lack of a decent denoiser and a poor upscaling solution.

If the outlook is bleak at this point, I'd say that you should check out the Direct and see Quake 2 RTX in motion. This was the original path tracing showcase released by Nvidia and it eventually received updates to make it run on any GPU that supports hardware RT. Again, AMD hardware only receives a TAAU solution but the nature of Quake 2's visuals and its less ambitious visual feature set means that the game looks good on PS5.

Intriguingly, the base performance numbers are impressive. We got a couple of built-in timedemos working and while 11.4fps and 10.7fps at native 4K on default settings are obviously very low, the fact that native 4K path tracing works at all on the PS5 is astonishing. And as you scale down, the numbers drastically improve. By keeping 4K output and using TAAU upscaling from 1080p, the frame-rate averages settle at 40.4fps and 37.8fps. And by engaging dynamic resolution scaling with a 25 percent minimum (meaning native 540p) Quake 2 RTX now runs pretty much at a locked 60 frames per second. 60fps path tracing on a PS5. That's worth shipping.

And I think that there is another mitigating factor I should point out. The RADV driver used by Linux has come on leaps and bounds in terms of its ray tracing capabilities, but there may be more to come. Beyond that, the PS5 itself features highly performant RT bearing in mind its spec and part of that comes down to lower level access than the standard DXR interface.

While it's hard to see that making any kind of path tracing project more viable for PS5, we should expect similar access to PS5 Pro. After all, we've already seen Codemasters display an F1 25 path tracing demo for the Professional.

With PS5 though, this was an interesting afternoon of testing - more for entertainment than anything else - but we'll be returning with some more Linux testing soon. I mean, how does PS3 emulation look on PS5? RPCS3 runs natively on Linux, it works on PS5 and I'll be reporting back on that soon.