I'll just add that PCB really means (Printed Circuit Board) and are flimsy and often times whimsical things to deal with, especially if you've got a board with a "Suicide Battery" that when the battery dies it kills the board, can't play the game anymore. If you're playing older games on even NON NEO games then PCBs are what you'd be slotting into a JAMMA RIG, otherwise that was the whole concept behind MVS (Multi Video System) Carts, you slotted a cart into a PCB board with the slots allowing access by way of the respective cartridge... which is why so many people were pissed off about SNKP not releasing SVC Chaos "Officially" on the MVS format and only on a PCB... meaning MVS users would have to detatch their 1, 2, 4, or even 6-Slot PCBs off the JAMMA RIG, and slide a single game into it, only to replace later... just a bunch of B.S. *Thus a lot of us on that note got Revision C+ GMVS carts of it due to principle of the matter. *I think it's great however, that SNKP got smart and released METAL SLUG 5 and KOF 2003 as "Official" MVS Carts, it's just too bad the ride has finally come to an end on the Neo Hardware after a bitchin' 14 year run... I was hoping to see it though two decades but it didn't happen. Anyhow that's the differences I know of between CARTS vs. PCB.
MERCENARY X99