Nvidia today announced that Resizable Base Address Register (BAR) support is now available for RTX 3060 graphics cards and RTX 30 Series laptops. That’s earlier than the company anticipated, but it comes with a caveat, because its other desktop GPUs aren’t expected to receive drivers that support the technology until “late March.”
AMD was first to market with Resizable BAR support, which it branded as Smart Access Memory, but the technology is actually part of the PCIe spec. The feature expanded to the Intel Z490 platform in December 2020, and Intel told us earlier this month that it was ready to support Nvidia graphics cards as soon as possible.
So what is Resizable BAR? Nvidia explained in today’s announcement that it’s meant to let the CPU “efficiently access the entire frame buffer” by enabling as-needed transfers of textures, shaders, and geometry that can be processed concurrently rather than queued up. The result: improved performance. Maybe. In a few titles.
Intel’s GM of premium and gaming notebook segments, Fredrik Hamberger, told us that Resizable BAR support could lead to performance gains of 5-10% in some games. Nvidia said that “the performance benefits of Resizable BAR can vary substantially from game to game,” however, and that some titles actually performed worse. Support is also available for AMD CPUs.
This led the company to say that it “will be pre-testing titles and using game profiles to enable Resizable BAR only in games where it has a positive performance impact.” That’s resulted in RTX cards supporting just eight titles, including Assassin’s Creed Valhalla and Red Dead Redemption 2, with the initial driver that was released today.
Nvidia said it plans to expand Resizable BAR support to additional games when it rolls the feature out to more of its 30-series graphics cards next month. For now, though, it seems like the company’s support for the technology will only affect a very small portion of its customers. Let’s see if it raises the (resizable) bar later on.
