This week TechARP discusses the NVIDIA GPU Ex BIOS setting, you can read about it over here.
NVIDIA GPU Ex is an NVIDIA chipset-specific BIOS feature. The name is purportedly a truncation of "NVIDIA GPU Extra", hinting that it improves the performance of NVIDIA graphics cards.
According to NVIDIA, this BIOS option is a toggle for chipset-specific optimizations that improve the performance of NVIDIA graphics cards when NVIDIA GPU Ex graphics drivers are used. All NVIDIA ForceWare Release 90 or newer graphics driver support NVIDIA GPU Ex.
When set to Enabled, the BIOS will enable chipset optimizations for NVIDIA graphics cards when used with graphics drivers with NVIDIA GPU Ex support.
When set to Disabled, the BIOS will disable chipset optimizations for NVIDIA graphics cards.
When set to Auto, the BIOS will enable the chipset optimizations when it detects the presence of an NVIDIA graphics card when the computer boots up.