28 years later, hacker fixes rampant slowdown on SNES‘ Gradius III

Many gamers of a certain age (this author included) remember the early ’90s disappointment of buying the SNES version of hit arcade shmup Gradius III. In magazine screenshots, the game’s huge, colorful sprites were a sight to behold, comparable to the 1989 arcade original. In action, though, any scene with more than a handful of enemies would slow to a nearly unplayable crawl on the underpowered SNES hardware.

Now, Brazilian ROM hacker Vitor Vilela has righted this nearly three-decade-old wrong with a ROM patch that creates a new, slowdown-free version of the game for play on SNES emulators and standard hardware.

The key to Vilela’s efforts is the SA-1 chip, an enhancement co-processor that was found in some late-era SNES cartridges like Super Mario RPG and Kirby Super Star. Besides sporting a faster clock speed than the standard SNES CPU (up to 10.74 Mhz versus 3.58 Mhz for the CPU), SA-1 also opens up faster mathematical functions, improved graphics manipulation, and parallel processing capabilities for SNES programmers.