PS5 can run PS3 games through Linux and RPCS3, but the CPU is still the big limit

Digital Foundry has tested PlayStation 5 as a PS3 emulation machine by running Linux on the console and using RPCS3 natively. The result is an interesting look at what Sony’s current hardware can do when it is pushed outside its normal system software, though this is not an official Sony backward compatibility feature and requires a PS5 running exploitable firmware.

The setup used Linux installed on an SSD in the PS5’s M.2 slot, with RPCS3 running as a native Linux application. That means the emulator was not going through Proton translation. Digital Foundry also used the RADV driver, allowing the PS5’s AMD based hardware to run PS3 games through a PC style emulation setup.

Some PS3 games can reach much higher resolutions, but Cell processor emulation remains difficult

The results depend heavily on the game. Some earlier or less CPU heavy PS3 games scale well on PS5. Ridge Racer 7 reportedly ran at 4K and 60FPS, which is a major jump over the original PS3 experience. Resistance: Fall of Man also reached 4K output, although it still showed frame pacing issues.

Heavenly Sword delivered one of the more impressive tests. The original PS3 version could fall below 30FPS at 720p, but Digital Foundry was able to run it close to 30FPS at 5120×2880. That is far beyond the game’s original resolution target and shows that the PS5 GPU has plenty of room for higher output in some titles.

The harder games show why PS3 emulation is still complicated. GTA IV and Metal Gear Solid 4 did not benefit much from higher resolution settings because the bottleneck was not the GPU. The problem was CPU emulation, especially the challenge of replicating the PS3’s Cell processor and its SPUs.

Killzone 2 also struggled. Digital Foundry linked this to the game’s heavy use of SPUs for animation, AI, and post processing. Killzone 3 performed better after MLAA was disabled through RPCS3 patches, often reaching 30FPS at 4K, although some scenes still dropped into the 20s.

The MotorStorm games looked more promising. The first MotorStorm ran at 1440p with a 30FPS target, while MotorStorm: Pacific Rift reached 4K at 30FPS. MotorStorm: Apocalypse also came close to its original 30FPS target once MLAA was turned off.

The broader takeaway is clear. The PS5 has enough GPU power to push many PS3 games far beyond their original output. Higher internal resolutions such as 4K and even 5K are possible in some cases. But the console’s Zen 2 CPU still has trouble with games that rely heavily on the Cell processor’s unusual design.

That makes this test both exciting and limited. It shows that PS3 emulation on PS5 hardware can work, but it also explains why official PS3 backward compatibility is not simple. Sony cannot just brute force every PS3 game without solving difficult CPU emulation problems.

Digital Foundry suggests that full speed PS3 emulation may be more realistic on next generation console hardware, assuming similar Linux access is possible. For now, PS5 Linux and RPCS3 can deliver impressive results in selected games, but it is not a clean or universal solution for the PS3 library.