*** Official Radeon HD5800 Series Overclocking Thread ***

[Chickenfeed]

I think 5870 Cypress XT's can require different 3D voltages to keep stability at 850mhz, and that this is why we're seeing stock volts anywhere from 1.1v to 1.17v for 5870s.

That would explain a lot.

I've actually had issues at 900 at stock volts in GTA ( hard lock ; funny thing is Crysis doesn't lol ) I am not sure how high I can get without upping the voltage but I am content with the card as is now all around so I won't press the matter anytime soon.

My XFX has a bios with 3d voltage of 1.1625 by the way. I might try manually lowering to see how low it scales at stock core clock out of curiosity.