When playing PS2 game using PS4 emulator, it works null null at 60 fps - GIGAZINE
PS4's with FW4.05 & 4.55 can now play PS2 backups/ISO images!! - Hackinformer
Performance Analysis: PlayStation 2 emulation on PS4 | Eurogamer.net
GitHub - xXxTheDarkprogramerxXx/Ps2-Classics-emulators-for-Ps4: Ps2 Classics emulators for Ps4, this will allow you to use many different versions of emulator, which could improve or decrease the compatibility
EP 5) How to Run PS1, PS2 & PSP Games on a PS4 (9.00 or Lower!) - YouTube
New graphics comparison shows upscaled 1080p PS2 emulation on the PS4
PS2 games on PS4: 7 gems that need a remake | Red Bull
PlayStation 4 to get PS1/PS2 emulator - Report - GameSpot