Resizable BAR
Definition
PCIe feature letting CPU access all GPU memory at once.
Detailed explanation
Resizable BAR is a PCI Express feature that allows the processor to map a larger portion of graphics memory at once instead of working through a small legacy window. Supported games and workloads may gain performance by moving assets more efficiently, though results vary and some titles show little change. Enabling it requires compatible CPU, motherboard firmware, graphics hardware, and a current display package; firmware often labels the prerequisites Above 4G Decoding and Re-Size BAR Support. Confirm support across the whole platform before changing settings. If the PC stops booting or performance becomes less stable, restore the previous firmware values. Updating the graphics package alone cannot enable the feature on unsupported hardware.