Since SteamOS 3.5 finally released into stable, I’ve been looking forward to try out PS3 emulation on the Steam Deck, especially the Uncharted series & MGS4.

Long story short, performance was rather subpar, with frequent FPS drops.

Looking around, I came across this post on Reddit:

https://www.reddit.com/r/SteamDeck/comments/16ydaoz/mgs4_on_rpcs3_with_full_visual_effects_on_the/

After applying the tweaks referenced there, I really did saw a boost of a few more additional frames, but the real improvement is that the frametimes become more even, resulting in noticeably less stuttering.

With a 50 % resolution render scale, Uncharted 1 can be considered playable on the Steam Deck, IMHO.

Hope these tweaks help you guys out, too!