An Xbox Series X can now run PlayStation 5 games, but there’s a catch

In a YouTube video that went live on September 8, developer Devran Cosmo Uenal booted the PlayStation 5 version of Quake II on an Xbox Series X and played it with an Xbox controller. But the game was running through PS5X, Uenal's Xbox port of the open-source PS5 emulator KytyPS5, and he has gotten three more PS5 games working alongside it.

The fact that he's managed to get PS5 games running on an Xbox at all is super cool, but there's a catch: PS5X only works in the console's official Developer Mode, where Microsoft's documentation caps games at 5GB of memory. That unfortunately rules out the majority of current-gen games, and there's no public download for anyone else to try yet.

Sony and Microsoft built their current consoles around closely matched AMD hardware. Both of them have eight Zen 2 CPU cores, RDNA 2 graphics and 16GB of GDDR6 memory, and PS5 games are compiled for the same x86-64 processor architecture that PCs use. That means the KytyPS5 emulator can run their code on the host CPU instead of recreating the PS5's hardware in software. Its developer calls it a compatibility layer and, practically, it behaves more like a translator, converting what a PS5 game asks for into something a PC can understand.

KytyPS5 translates the PS5's graphics commands and recompiles its shaders for Vulkan. As a result, it needs a Vulkan 1.3 graphics card on PC, but Xbox Developer Mode only supports DirectX 11 and DirectX 12. "Since Vulkan isn't supported, everything needs to be translated to DirectX," Uenal wrote in the YouTube video's description, where he also admitted that AI was involved in the work. As VideoCardz pointed out, that means fixes the KytyPS5 team makes to its PC renderer have to be adapted before PS5X can use them.

Uenal's video also describes PS5X as a "research project" for "running PS5 homebrew and game backups" on a Series X in Developer Mode. He claims that it doesn't include any PS5 firmware or decryption keys, and KytyPS5's documentation tells users to stick to game files they've obtained legally. Dodging copy protection is ultimately what killed the Switch emulator Yuzu, whose makers settled a Nintendo lawsuit back in 2024 by paying $2.4 million and shutting the project down. The team behind the PS3 emulator RPCS3 lists KytyPS5 and SharpEmu as the two active open-source PS5 emulators that can boot games, and warns players about scam sites posing as real ones.

At the time of writing, PS5X runs the PS5 versions of GEX Trilogy, Hellboy: Web of Wyrd, Marvel Cosmic Invasion and Quake II, and all four are compatible with Xbox controller inputs. Some of them have working sound, and TweakTown reckons that Quake II runs at roughly 25 to 45 frames per second in Uenal's footage. It's worth noting that these four games are also sold on other platforms, so there's no sign yet of PS5X running a PS5 exclusive, and Uenal admits that it's early days and that compatibility is limited.

Android Authority reported on September 28 that KytyPS5 now goes in-game in a variety of PS5 titles on PC, and that one user had shown Marvel's Wolverine reaching its main menu, in slow motion, on a machine with an NVIDIA RTX 5090. That clip didn't show any gameplay, however, and it's not clear whether it used the standard emulator build. PS5 emulation on PC is becoming more viable by the week, but it's still an extremely nascent field, and PS5X only inherits any progress once each fix has been rebuilt for DirectX and squeezed into a far smaller memory budget.

Microsoft limits games in Developer Mode to a relatively small 5GB of memory, and apps to 1GB. Requests for more memory than that allocation fail. In contrast, a retail Series X game gets 13.5GB of the console's 16GB, while the remainder is reserved for the console's OS. That leaves PS5X to work with about 37 percent of the memory a normal Xbox game can use, making it an obvious no-go for big current-gen releases. Microsoft only lifts this cap when software runs via the Visual Studio debugger, which is a setup designed for devs testing their code.

Microsoft blocked emulators entirely in Xbox's normal retail mode back in 2023, its rationale for doing so being a store policy that bans products that emulate a game system. It then started bringing down the ban hammer and reportedly handed out 15-day suspensions to players who found a workaround. Since then, players who want to play PS2 or GameCube games through, say, Dolphin, the most popular GameCube emulator, have had to rely on Developer Mode instead. But a console in that mode can't load retail games until it's switched back.

Xbox Series X comes with the same Zen 2 architecture and RDNA 2 graphics as a PS5. It's also got the same amount of memory, and PS5X can use less than a third of that. But none of this really matters because of the memory cap. There's no real workaround to this without a jailbreak, meaning Xbox players won't benefit from the progress being made on the PC. Sure, PS5X is interesting, but it'll remain a cool little curio rather than anything substantive players can use.

If you're interested in checking out PS5X and similar emulation projects, you should exercise caution. Scammers are capitalizing on the interest these projects receive, such as releasing malware under similar names like PCS5X to try and trick players into downloading it.