Which handheld runs PS2?

Not viable on this hardware, regardless of settings or custom firmware.

Some titles run untouched at native resolution; most popular ones mean a trip to the settings menu.

• A few titles need 1x resolution to hold full speed.
• Some do not work well no matter what is changed.

More variable than GameCube. A per-title question rather than a yes.

• In one 20-title test, 17 ran at 30+ fps on default settings and 3 needed specific emulator configuration.
• Demanding exclusives may need the rendering resolution dropped to hold full speed.

Around 90% of the library runs with upscaling to 1080p and widescreen hacks enabled.

Runs reliably as part of the device core library.

Runs, but expect 30-45 fps on many titles rather than the original 60.

• The Snapdragon 865 holds peak clocks for roughly 90 seconds before thermal throttling begins.

Roughly 85-90% of the library at full speed without significant tweaking.

• Most titles handle 2x upscaling without slowdown.
• Fan noise is noticeable under sustained load.

Full speed, including titles that were demanding on earlier Android handhelds.

• Dolphin and AetherSX2 run demanding titles at 2x to 3x native resolution.

Handles the library upscaled to 1080p, without much fiddling or compromise.

Demanding titles run at 1.5x to 2x native resolution.

• Need For Speed: Most Wanted is cited as an example of the heavier end running smoothly.

Runs as it would on original hardware, upscaled to 720p.

• Metal Gear Solid 3, Ratchet & Clank and Grand Theft Auto III perform exactly as on hardware.
• x86 with active cooling avoids the sustained-clock problem that limits mobile SoCs on PS2.