Resizable BAR is an optional PCI Express interface technology. As you move through a world in a game, GPU memory (VRAM) constantly transfers textures, shaders and geometry via many small CPU to GPU transfers. With the ever-growing size of modern game assets, this results in a lot of transfers.

Should you enable resize bar?

Resizable BAR is just like that: instead of accessing 256MB chunks of VRAM, it allows your CPU to access the GPU's entire framebuffer, so it can send more assets at a time. This, in turn, boosts performance because your graphics card doesn't have to wait around as long—at least, in theory.

What is resize bar support?

Nvidia is launching Resizable BAR support today, a feature of PCI Express that can boost frame rates in certain games by up to 10 percent. Resizable BAR works by unlocking access to the full graphics frame buffer, instead of limiting it to 256MB block reads.