I want to throw my 290x's at the wall! 700kH/s :O
Last week I decided to jump in to the Litecoin game. I picked up a Gigabyte GA-990FXA-UD3, Sempron 145, 4GB memory & Corsair HX850. I also have 2 Gigabyte Radeon R9 290x's + 2 Sapphire Radion R2 290x's.
I installed Windows 8.1 with AMD Catalyst BETA 13.11. I configured CGMiner and cannot get more that ~700 kH/s on a 290x!!!.
My thread concurrency is set to 28600. CGMiner just stalls at a black screen if I set the thread concurrency to 32765.
I've tried with just single card and I cannot get any faster than 700kH/s and doesn't load with with thread concurrency at 32765.
I read somewhere that it may be because of the Gigabyte cards to I just got a pair of Sapphire 290x's today. I replaced the Gigabytes with the Sapphires and the speeds are only marginally better (709 & 740). I still can't get CGMiner to load at 32765.
I also have another PC with a i5 and 16GB of memory...I put the Gigabyte card in there and it still tops out at 700 and crashes at 32765.
Here is one string (I also have a 5850 in there, but I removed it to troubleshoot):
start cgminer -d 1 --scrypt -I 20 -g 1 -w 512 --thread-concurrency 28600 -o WEBSITE -u USER -p PASS