Increasing voltage on hd 6870

[vibrantxxninjas]

hey everyone,
i OC'd my sapphire 6870 to 975 core and 1150 mem when it became unstable until i drop the core 5MHZ.
so my question is by how much should i increase the voltage by for each time i feel i should increase it for stability?
thanks

 

[henydiah]

yes when you overclock it you must be increased voltage from Afterburner, and increase speed fan gpu . after that you can test the stability with kombustor

 

[GObonzo]

running 975MHz core & 1175MHz mem with stock voltages stable. I plan on raising voltage and clocks a lil more but want to see more response from those already pushing these cards first.
I've seen reviews saying they pushed voltage up to 1300 but I'm nervous upping it at all. 1200 seemed high for me and 1000MHz/1200MHz wasn't stable even at 1200. how about some input?!
how much should we be pushing the voltage up with each increase and how far is considered safe for these newer 6870s?

 

[GObonzo]

set back to 1000MHz core and was just watching as FurMark ran, my GPU gadget is showing voltage still @ 1174 though MSIAfterburner settings are @ 1200. I'm guessing Afterburner can't control the voltage on this card for some reason. what's another way of accessing the voltage without modifying the card bios?

 

[vibrantxxninjas]

set back to 1000MHz core and was just watching as FurMark ran, my GPU gadget is showing voltage still @ 1174 though MSIAfterburner settings are @ 1200. I'm guessing Afterburner can't control the voltage on this card for some reason. what's another way of accessing the voltage without modifying the card bios?

sorry for the late reply, you have to go into msi afterburner settings and tick 'unlock voltage control'

 

[GObonzo]

sorry for the late reply, you have to go into msi afterburner settings and tick 'unlock voltage control'

already had done. can't even access the voltage slider without enabling voltage control in Afterburner first. have tried Afterburner, Trixx, changing BIOS options, flashing to Black Edition of this card, there is no way to adjust voltage I can find. limit is 950MHz/1200MHz with the stock 1.1745v for now.

 

[lhaskew]

If it is a non-reference card, it may not have a voltage controller. Some companies follow what ATI recommends when building the card and some don't. The reference design had a voltage controller, but some companies did not include this feature. It was most likely an attempt to cut cost.