Bitcoin Forum

Hi,

I've been using dual Radeons since HD 5970, and still have 2 5970s for reference, and in this case with 2x 5970 the 4 GPUs run with identical hasrate and temps between 70 and 80c. Voltage, mem and GPU clocks at stock.

With 7990 it's a very different story. One card runs perfectly on stock with around 700Kh/s per GPU, the second runs at 90c with mem/GPU at 50% clock! It's the same on 3 different mobos. Switch to 5970 and both cards and all gpus behave the same - and at normal temps.

I'm baffled, as I'm only able to reproduce this behaviour with Scrypt - no such asymmetry with Milkyway@Home, Seti@Home, Einstein@home, etc. 

Anyone else around with 2 or more HD 7990 scrypting on same mobo - would be great to hear your story with these cards.

FYI: I have open air testbeds, so free airflow, and room temp is 10c. No change in behaviour including Catalyst 13.9.

M

I had a similar issue but it was only because of the airflow. It was always the card that was in the lower pcix slot that it was getting hotter.
The problem is always in the same gpu for you?