I'm really struggling here. I got my R9 290 Tri-x OC cards yesterday and started installing them in 4 different computers. However, what I'm finding is that the cards have a consistent drop off and I mean in an extreme way and I have been unable to figure out why.
First some details. I've moved the "little switch" to both positions on the cards with the same results. I'm running BFGMiner 3.9 and I'm using a bat file with the following settings (I've used configs to), but keep in mind I've tried a hundred different settings with the same results.
-I 20 -g 1 -w 256 --lookup-gap 2 --gpu-memclock 1500 --gpu-engine 1000 --thread-concurrency 28456 --gpu-powertune 20 -S opencl:auto --auto-fan
The results are consistently repeatable. The first 30 seconds to a minute is blazing fast with speeds greater than 1 mh/s, then there is a steady drop down to essentially nothing meaning lower than 300 kh/s.
For instance, I let two of the cards run in a computer over night and when I checked them this morning the speed was 140 kh/s per card. On the one system where I just put one card it as at 280 kh/s in the morning.
I'm totally new to overclocking and the software to do it so bare with me here. I installed TRIXX today to mess with the settings a bit to see if I can figure out what is going on but it seems the cards simply ignore the settings after a few seconds.
EDIT: I struck out the part on the fan having a mind of it's own because I was actually running the miner in the background and forgot so BFGMiner was taking control of the fan again and slowing it down. When I shutdown BFGMiner the fan stayed at the speed I set.
It seems the cards are marching to their own drummer so-to-speak and I haven't figured out what is going on with them yet. I've tried four different cards so far though and they are all acting the same way in two different computers.
One of the computers have 8 gig of RAM the other 16 gig of RAM. EDIT: Each computer is running Windows 7 x64.
I'm puzzled though. Has anyone else run into something like this?