Due to the popularity of the Sega Saturn in the Japan, much more was done with the system there than what would ever reach Western shores. Amongst those additions was the 1 MB and 4MB RAM expansion carts which could expand the stock hardware’s original 2mb “working RAM” for expended gameplay experiences.
These expansion devices plug into the rear cartridge port of the system and for all intents and purposes, simply added more system RAM which the Saturn could utilize for playing software. What this does is to allow the console to load more “active” game files into system memory when playing. When playing the game, active code such as sprite animations are loaded into this working RAM to be displayed on screen. The rest of the game data is loaded as needed. This creates a bottleneck limiting only those 2mb of the total game which can be active at any given time. When you plug in a RAM expansion cart, you are simply adding additional working RAM which the system can actively utilize (3mb for the 1mb expansion cart, and 4mb for the 2mb expansion cart). Most games that utilized this feature used it to increase the number of on-screen animations happening at any given time. Clever programming could work around this for most titles, but where it is most evident is in 2D fighting games where extra frames of animation could make a very visible difference and it was harder to program around the RAM limitation. As such, the majority of games which utilize this feature are 2D fighting games. This is an over-simplified explanation but I believe it creates the general understanding most people need.
These expansion carts were never officially released in the West where the Saturn performed poorly on the market, but were popular enough to come in several sizes. The most commonly utilized of these was the 1mb and 4mb varieties. Some Western games even supported the carts but this was never advertised, most famous of these would be Marvel Super Heroes which can optionally take advantage of the 1mb expansion, but does not require it. If you were to utilize this cartridge when playing it, you will see smoother and more detailed animations when playing.
Unlike Marvel Super Heroes, some other games didn’t make the cart optional, a testament to the success of this add-on, unlike many of Sega’s expansion attempts in the West. The problem with titles which do require the cart is the simple fact that they are completely unplayable without it. Fortunately, for us modern Western gamers, these carts are now cheap and easy to get on sites such as eBay. Furthermore, certain versions of the modern Pseudo Saturn Kai cartridge offer this functionality such as our 5 in 1 version (available in our shop) which allows you to switch between standard, 1mb, or 4mb modes.
The following is our aggregated list of games which either optionally use, or require the RAM expansion cartridge:
1MB RAM EXPANSION CART:
Astra Superstars (Optional)
Cotton 2 (Optional)
Cyberbots (Optional)
Fatal Fury 3
Fighter’s History Dynamite
Friends: Seishun no Kagayaki (Optional)
Groove On Fight
King of Fighters ’96
King of Fighters ’97
King of Fighters, The: Best Collection
KOF Double Pack: King of Fighters ’95 & ’96
Marvel Super Heroes (Optional)
Metal Slug
Noel 3 Limited Edition (Optional)
Noel 3 (Optional)
Pia the Carrot (Optional)
Ragnagard
Real Bout Fatal Fury
Real Bout Fatal Fury Special
Real Bout Garou Densetsu Best Collection
Real Bout Garou Densetsu Special
Samuari Showdown IV
Samurai Showdown III
Samurai Spirits Best Collection
Samurai Spirits: Amakusa Kourin
Samurai Spirits: Zankurou Musouken
Super Real Mahjong P7 (Optional)
Super Real Mahjong P7 P’s Club Limited Edition (Optional)
Waku Waku 7
4MB RAM EXPANSION CART:
Astra Superstars (Optional)
Cotton 2 (Optional)
Cyberbots Full Metal Madness (Optional)
Dungeons & Dragons Collection
Fighter’s History Dynamite
Final Fight Revenge
Friends: Seishun no Kagayaki
Groove on Fight
King of Fighters ’96
King of Fighters ’97
King of Fighters, The: Best Collection
KOF Double Pack: King of Fighters ’95 & ’96
Marvel Super Heroes (Optional)
Marvel Super Heroes vs Street Fighter
Metal Slug
Noel 3
Noel 3 Limited Edition
Pia the Carrot (Optional)
Pocket Fighter (Optional)
Real Bout Fatal Fury Special
Samurai Spirits Best Collection
Samurai Spirits: Amakusa Kourin
Samurai Spirits: Zankurou Musouken
Street Fighter Zero 3
Super Real Mahjong P7
Vampire Savior
Waku Waku 7
X-Men vs. Street Fighter
NOTE: These lists may not be exhaustive.