GPU Bank Flip; Also known as Graphics Processing Unit, is designed for Crossfire Technology from ATI, certain Circuit Boards which support this is set as Disabled as default for user select for crossfire in later cards, which allow the two ati cards to switch from one unit to the next to use and combine both 1 gb or 512 mb of ram on the cards itself. doing so will allow greater speeds as well as software performance. though this is only used when using a game that needs more Random Access Memory. this setting is only required if you have the proper RAM and Crossfire technology, though on certain motherboards which only have one PCIE still remain with that option in the bios which is only intended for at least 2 gigs of ram with one gig of RAM on the Graphics card processing Unit, Single, which in return maximizes the Use of RAM from the OS to the Card. though this varies from which Operating System you use.