Bitcoin Forum

Hi.
I'm using a HD6870 and a HD5870, both of them are overclocked.
When I open MSI Afterburner I can change everything of my 6870, but when I switch to GPU2 I'm only allowed to change the Mem-clock, Core-Clock and Fan speed. I can't even see how much voltage it has and I have no idea why.
It's running at 930/300 stable though so I guess its not that bad.

Go to settings and check "unlock voltage"

Also, I believe that if your cards are not identical to the ATI reference design or MSI design then MSI Afterburner won't give you voltage options, as it doesn't know how your card controls the voltage.

I don't get voltage options with my XFX cards, even if I unlock the voltage option or flash the cards with a different BIOS.

It's unlocked, that's why I can control the voltage of my 6870.
And I dont think it depends on the brand. They're both from XFX and the 6870 works fine. A GTX460 by Gigabyte also worked fine.

It depends on the design of the card. The one that works is an ATI reference design, the ones that do not work are likely of a non-reference design. Use Sapphire Trixx, it is known for allowing for the adjustment of the voltage regulators on non-reference cards.

So it might work if I flash the card with another BIOS? The MSI and ASUS one seems to be unlocked.

Had the exact same problem on a Sapphire HD5770.
First I thought it was Win7 permissions that didn't allow edition of AB config file.
But that didn't do it.

Finnally I tried ATI's Trixx. Couldn't change voltage, but allowed me to overclock far beyond 960 cap. Now I have it on 1050 and really under 60°C.

At 1050 with Stock Voltage and 60°C?! I have 78°C and 940 Core, but mine is above the 6870 so it might be hotter because of that. Do you use watercooling?
Edit: Oh i just read its a 5770, nevermind.

No, your card uses a different voltage regulator to the ATI reference design.

Use MSI Afterburner with AMD GPU Clock tool, thank me later  ;)

You obviously have a card that consumes no power to run!  :D

You will need to unlock unofficial overclocking by editing the .CFG file in the afterburner installation directory.
A complete guide can be found on the BitClockers.com  (http://BitClockers.com)forum
http://bitclockers.com/forums/index.php?topic=5.0 (http://bitclockers.com/forums/index.php?topic=5.0)

This will allow much higher overclocking frequencies as well as voltage adjustments if your card is supported.

It depends on the voltage regulators they use on the Cards. My Asus Ares 5870x2's are custom cards, and they work fine with afterburner.

Okay, thanks for the help. Seems like the only way to increase voltage on this one is a hard mod, but I'm not gonna do that.
I tried to push it a little bit and the card is now running stable on 990/300 (I'm not kidding) for some hours.
Getting 435Mhash/s out of it.

300 memory clock?

Why?

I had one of my 5850's running at 970/1250...but 990/300? Just why?

Lower Temps, Duh

And saves ~15=20 watts. Personally havent experienced improved H/s though.

My hash rate INCREASES when I drop the memory clocks down. Memory clock = (core clock / 3) + 14 seems to give me the best speeds for my 5850's