By default RivaTuner hides MMIO memory ranges into kernel address space to protect itself from unsafely designed memory scanners like PunkBuster anticheat system, which can cause unpredictable results due to unauthorized access to hardware I/O ports mapped memory ranges. Set this value to 0 disable this protection.

[b]Tip:[/b]

This protection increases CPU load when RivaTuner is accessing hardware. Disable it if you're not affected by PunkBuster's memory scanning issues.