The main bottleneck in PS2 emulation is emulating the Emotion Engine multi-processor on the PC x86 architecture. Since September 2016, PCSX2 is partially compatible with PlayStation games. Additionally, PCSX2 requires a genuine copy of the PS2 BIOS, which is not available for download from the developers due to copyright-related legal issues. Different plug-ins may produce different results in both compatibility and performance. These are the graphics, audio, input controls, CD/DVD drive, and USB and FireWire (i.LINK) ports. PCSX2, like its predecessor project PCSX (a PlayStation emulator), is based on a PSEmu Pro spec plug-in architecture, separating several functions from the core emulator.
