Quote from: drakoin on January 22, 2014, 07:07:46 PM

Quote from: HumbleMiner on January 22, 2014, 06:07:44 PM

Quote from: dragonmike on January 22, 2014, 06:02:33 PM

- vddc shows 1.2v in the web stats interface but max 1.14 in my conf file... And ccc seems to confirm max at 1.14.

Undervolting via cgminer rarely works. You can use MSI Afterburner in Windows in order to check if the voltage control is unlocked and can be controlled by software. If not - you'll need to flush you GPUs' BIOS in order to unlock.

We have explored that topic a lot in the past weeks.

Have a look at this thread about
(A) optimizing with stock voltage,
(B) undervolting, potentially with your own modified BIOS, and
(C) undervolting and underclocking to a certain sweet spot

The reason for doing this is NOT to blindly increase the khash/s. But to save money by using much less electricity.
(C) results in amazing khash/Watt efficiency: Almost 3 khash/Watt for the whole rig, and 4.0 khash/Watt for the GPUs only.

Very important for people in countries with high electricity prices, and those mediocre weeks with low coin output.

I suggest to jump into posting #37 now - but if you want to try, please read the whole thread. More reading, but less tears :-)

Quote from: HumbleMiner on January 22, 2014, 06:07:44 PM

This is potentially dangerous since that might brick your GPUs.

Exactly. That's why I like the VBE7 approach, to not just flush any other BIOS, perhaps even from a different vendor, but to use the original BIOS, and just tweak 3 values. Posting #45 gives such a BIOS, and how I created it.

Still, there is enough danger left. Do it at your own risk - and not in all of your GPU cards at the same time.

Wink

---
P.S.: Let's spread the word, imagine the altcoin network starts saving 1/4, 1/3 or even 1/2 of electricity.

Can I ask how you work out the kH/Watt for the GPU's only?

jam3zs

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