 |
December 05, 2013, 09:34:53 PM |
|
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
|
