Set the option to "Yes" if you want to clear ESCD (Extended System Configuration Data) NVRAM. After it was done in the next boot, it will be back to "No".

The BIOS updates the ESCD each time the hardware configuration changes, after deciding how to re-allocate resources like IRQ and memory mapping ranges. After the ESCD has been updated, the decision need not be made again, which thereafter results in faster startup without conflicts until the next hardware configuration change.