RetroArch - QuickNES

QuickNES, is a highly accurate and feature-filled emulator for the most popular '80s home videogame console, with support for tons of features. Began as very simple sometime in 2004. This is by far the fastest emulator for this console that you will find. If you are in need of an NES emulator with the least amount of CPU overhead or you have very dated system specs, QuickNES is the emulator of choice. The latest QuickNES made by Christopher Snowhill (AKA 'kode54') is a fast and heavily modified variant of the code originally made in 2003-2005 by Shay Green (aka 'Blargg' on his website or 'gblargg' on GitHub). Chris added his own open-source Windows front-end to his QuickNES core. 'Blargg' is the one who developed the strident emulation accuracy tests for many emulators striving to simulate the GB and GBC hardware as closely as possible. He also created his own NTSC Filters, which replicate the analog signals that the consoles output to the TV, and has been used in many emulators for the NES, SNES and 2D Sega consoles (SMS & GG). Christopher Snowhill's core of QuickNES, that was first uploaded to GitHub on January 11, 2010, was abandoned on early December 2014. However the libretro core, derived from that old core on December 9, 2012, is still active, and other programmers have introduced many improvements including adding more mappers.