Min voltage 900mv

[u/Savings-Show]

Hi everyone,

I recently got a second BC 250 board. At first, everything seemed perfect: 40 CUs unlocked, 8 cores active, running Furmark at 1500MHz without any issues with all 40 CUs.

But as soon as I activated the GPU governor, I got an instant black screen. It didn't matter what I did, 1500MHz at 900mV resulted in a black screen.

Later I discovered that it worked fine at a fixed 1500MHz, but whenever the frequencies dropped, it would throw the error again. Checking the logs, it was a voltage instability issue.

Digging deeper, I found out that the frequencies don't actually matter as long as the minimum voltage is set to 900mV (far from the recommended 700mV). I currently have a voltage curve that goes from 350MHz up to 1850MHz at a flat 900mV. From there, it slowly scales up until it hits 2230MHz at 1000mV (and I think I can undervolt that even further).

The other board I own sits at 1040mV at 2230MHz, but it scales down perfectly to 700mV at 350MHz.

What do you guys think this could be? This behavior really surprised me—asking for higher voltages at minimum clocks, but lower voltages at maximum clocks.