It's one of the most crucial components of the PlayStation 5 experience - and yet right up until today's review embargo, we knew so little about it. Just how good is the backwards compatibility feature in the new console? Are we getting the same experience on legacy titles, including their performance limitations? Or is the news more positive: does PlayStation 5 mirror Xbox Series X's remarkable ability to dramatically improve existing games? Today, the mystery is finally solved and there's good news: PlayStation 5 backwards compatibility is excellent.
While there's the sense that it is a little rough around the edges in some scenarios and doesn't enjoy the full range of bonus extras Microsoft lavishes on Series X, PlayStation 5 has got it where it counts. If a game runs with an unlocked frame-rate or has the option to disengage a 30fps cap, you get the same transformative experience that you get on Xbox Series X. In fact, for reasons we'll go into later, the performance multiplier is actually higher when stacking up PS5 vs PS4 Pro against Series X vs One X. On top of that, there's the same revelatory increase in CPU performance too, meaning that the often lacklustre 'high frame-rate' modes seen in many PS4 Pro games now all lock to 60 frames per second.
All of this doesn't factor in that Sony has started to roll out specific PlayStation 5 patches for key first-party titles. We'll be looking at those more closely in future, but the headlines are simple enough: Sucker Punch's impressive Ghost of Tsushima now runs nigh-on flawlessly at 60 frames per second on PlayStation 5 - and it's simply brilliant. Equally as transformative is the PS5 patch for Bend Studio's Days Gone: again, it's a beautifully slick 60 frames per second. Surely it's only a matter of time before The Last of Us Part 2 sees a similar upgrade?
Returning to non-enhanced legacy titles, PlayStation 5 aces CPU-bound games just as well as Xbox Series X in almost all scenarios. Take the high frame-rate mode of Rise of the Tomb Raider (and indeed its sequel, Shadow) on PS4 Pro. In more challenging areas, the old Jaguar CPU cores simply couldn't cope, resulting in wildly variable performance. The same thing happens in Final Fantasy 15's Lite mode, and indeed in Hitman's Paris stage when frame-rate is unlocked. In all of these CPU-limited situations, PlayStation 5 delivers a totally locked 60 frames per second throughout. And of course, we also revisited Just Cause 3. It's legendarily CPU-bound, with big explosions and physics events sending frame-rate south of 20fps. Not surprisingly, PS5 doggedly locks to the original 30fps target from start to finish - and I have to say, I'm loving the game. Dark Souls 3? That'll be a locked 1080p60.
We also tested Crysis Remastered, which has a 1080p performance mode for PS4 Pro that essentially cuts back rendering resolution then unlocks the frame-rate. The Pro has a pretty torrid time with this - and in the village level in the second mission, performance drops to beneath 30 frames per second. Checkpoint stutters aside, PlayStation 5 renders the game out at a consistent 60fps. We can only hope that Crytek updates the game to unlock performance on all of its modes, including quality and ray traced options. We suspect that PS5 (and indeed Series X) will run all of these modes at full frame-rate.
GPU-wise, the mathematics look promising. PS4 Pro shipped with a 4.2TF GPU, while PS5's 10.3TF effectively delivers a 2.45x multiplier in compute performance. That's higher than the increase found on Series X, while the Pro titles also typically ran at lower resolutions than Xbox One X equivalent games. So, to put it bluntly - fewer pixels to render, and a higher multiplier in graphics performance means that the increase to performance vs Series X is improved. Consider Sekiro: Shadows Die Twice. It ran unlocked on PS4 Pro, and it utilised checkerboard rendering to hit 1800p, up against Series X delivering the same pixel count using native rendering. The bottom line is that PS5 hits 60 frames per second, while Series X is more of a 50fps to 60fps experience. In this case, Sekiro has an excellent checkerboard solution that's a great match for Xbox's native rendering - but the improvement to performance is noticeable.
There are more titles tested in the video embedded in this page (playing Knack at 60fps in high resolution mode when PS4 Pro could only hit the mid-20s is quite amusing) but the overall impression is that PS5 backwards compatibility delivers. However, it does lack the refinement and the thorough testing of Microsoft's solution. There's no real alternative to Xbox's innovative Auto HDR technology, and neither is 16x anisotropic filtering forced on in compatible titles in the way it is on the Series consoles. Warning messages also appear sometimes, when you boot a small selection of titles such as Sleeping Dogs Definitive Edition or Doom Eternal (both played fine for us).
But there is the sense that some games don't enjoy the full power of the new PS5 processor. The legendary disc version of Assassin's Creed Unity, with its unlocked frame-rate, produces a flawless 60 frames per second experience on Xbox Series X. The PlayStation 4 disc code is similarly unlocked, but certain areas of the game and depth-of-field-heavy cutscenes see performance plummet - sometimes as low as the mid 30s. Could it be that a compatibility mode is in place that limits GPU clocks to base PS4 spec? We know that this is an option available to developers now as they certify their new PS4 titles for PS5 play, and maybe that explains what is going on with AC Unity. Users of the patched game with its 30fps cap will be blissfully ignorant of this, of course.
Of course, it is worth stressing the limitations of backwards compatibility - and it's the same here as it was on Xbox Series X. Games that hit their performance targets on PS4 (be it 30fps or 60fps) will see no improvement on PlayStation 5. All games that run at 30fps will not run any faster unless the developer steps in with a patch - pretty unlikely for anything other than recent games. So to put it simply: no, you can't run Bloodborne at 60fps or indeed solve its dodgy frame-pacing issues.
Ultimately though, we had a huge amount of fun cherry-picking games from the PlayStation library and seeing how well they would run on PlayStation 5, especially when the results were so uniformly positive. The OG disc version of The Evil Within possessed truly awful performance - PlayStation 5 fixes it. Remember how poorly Until Dawn ran on PS4? Yes, that too runs at 60 frames per second on PS5. Looking to enjoy Assetto Corsa Competizione at 60fps? The resolution is very low compared to Xbox One X/Series X but that flat-out frame-rate is a lock even with 20 cars in the driving rain.
So, after some confusing messaging from Sony back in the day, followed by months of radio silence, the outlook is good. PlayStation 5 delivers comparable backwards compatibility with last-gen titles to Microsoft's equivalent feature. Sony's solution lacks some of the finesse and the sky-high resolutions of Series X playing One X versions, but clearly, it has advantages of its own. Before the arrival of Xbox One X in 2017, many Xbox games topped out at 900p vs 1080p PS4 equivalents. Series X can't break that 900p limit, but 1080p is what you'll get on PlayStation 5. PS4 Pro games may well have to contend with lower resolutions than One X equivalents, but in unlocked frame-rate scenarios, the boost to performance will be higher.
Really though, the key message to take from this piece is that PS4 users looking to upgrade to PS5 can relax. Your games will work - and then some.
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