MSI Afterburner

[BbBoS]

Hi all

On MSI Afterburner, I can't overclock my 4870 over 800Mhz Core because I can't adjust the voltage on it. I have selected for voltage to be unlocked / for me to control but it still won't let me change it. Anyone have any suggestions on how I can unlock it?

 

[Dublin_Gunner]

It could be your particular HD4800. They are not all created equally, and have different voltage regulators depending on model / brand.

Best way to check would be to use a BIOS editor like RBE, and check a dump of your bios (dump using GPU-Z)