Need help undervolting 290x

[enkidu78]

I have two different reference 290x cards, a HIS and a MSI and both wont allow me to undervolt.

When I set voltage in CGminer it says failed and using msi afterburner beta 3 18 if I set to -1 and apply it just goes back to 0.

From reading the 'whole' internet it would seem I need to flash the bios with an ASUS bios. I have downloaded ATIflash 417 from techpowerup but can someone help with what actual bios version I need to flash the cards with? Also am I doing anything wrong because surely it shouldn't be that hard?

 

[shankly1985]

In afterburner set the voltage 5 away from what you want. If for example me to get - 31 I first need - 35 once applied it will switch to - 31.

It's a known bug.

 

[enkidu78]

Doh!!! It worked! Cheers

So now GPU-Z is showing 0.960 at -31 under load... Whats -31 in real voltage reduction?

 

[nicnik]

-31mV so 0.031volts ?

 

[enkidu78]

Not a lot then...

 

[nicnik]

It's allot when you consider max you can increase is probably around 0.2 volts.

On stock clocks you might be lucky to get them working close to -50mV.

Also the 0.960v you see in GPU-Z is the idle voltage. Pretty sure on load the stock voltage should be closer to 1.2volts.