A secondary bus reset is a feature of the PCIe bridge (usually the chipset or CPU’s root port). The OS sets a bit in the bridge’s control register that asserts a reset signal on the entire bus segment. Every device on that PCIe slot—the GPU, any PCIe switches, even the physical slot’s power controllers—is forced into reset. This is electrically equivalent to unplugging the card and plugging it back in, except the 12V power remains applied. The GPU loses all configuration state: its Base Address Registers (BARs), its interrupt lines, its power management state.
If you have messed with overclocking or custom 3D settings and want to go back to the original state, use your GPU's control panel. graphics card reset
: Right-click the desktop → NVIDIA Control Panel → Manage 3D Settings → Click Restore Defaults in the bottom right. A secondary bus reset is a feature of