AMD announced Radeon Smart Access Memory (SAM) alongside the RX 6800 series as a feature to increase video memory available to the CPU. SAM is AMD's implementation of the resizable BAR feature found in the PCI Express specification. AMD Smart Access Memory is only available when using an AMD Ryzen 5000 series process and AMD Radeon RX 6800 series graphics card on a compatible motherboard. The feature was initially advertised as a 500 series motherboard exclusive feature but AMD has recently released the new AGESA v2 1.1.0.0 update which should enable support for SAM on B450 and X470 motherboards with a BIOS update.
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