AMD Ryzen 3000 and Older Zen Chips Don’t Support SAM Due to Hardware Limitation, Intel Chips Since Haswell Support it
AMD Ryzen 3000 “Matisse” processors primarily based on the “Zen 2” microarchitecture, as properly as more mature AMD processors centered on “Zen+” and “Zen” microarchitectures, do not support the company’s Clever Obtain Memory (SAM) characteristic currently being launched with Radeon RX 6000 collection graphics playing cards. SAM is primarily a branding of the Resizable Foundation-Deal with Register (Resizable-BAR) feature produced by the PCI-SIG which enables a processor to see a graphics card’s entire online video memory as a single addressable block, alternatively than by 256-megabyte apertures. Apparently the PCI-Express root advanced of Ryzen 5000 “Vermeer” processors introduce a PCIe actual physical-layer element termed total-rate _pdep_u32/sixty four, which is expected for resizable-BAR to work.
It receives more interesting—Intel processors have been supporting this attribute because the company’s 4th Gen Core “Haswell,” which launched it with its twenty-lane PCI-Categorical gen three. root-sophisticated. This implies that just about every Intel processor relationship back again to 2014 can technically assist Resizable-BAR, and it can be just a matter of motherboard suppliers releasing UEFI firmware updates for their goods (i.e. Intel eight-collection chipsets and later). AMD extensively advertises SAM as adding a 1-2% general performance strengthen to Radeon RX 6800 sequence graphics playing cards. Considering that this is a PCI-SIG function, NVIDIA strategies to incorporate guidance for it on some of its GPUs, too. Meanwhile, in addition to AMD five hundred-collection chipsets, even particular Intel four hundred-collection chipset motherboards started off acquiring Resizable BAR guidance by means of firmware updates.