i had to use this setting atm:
cgminer -o stratum+tcp://stratum.scryptguild.com:3333 -u aztecminer -p 123 --scrypt -I 13 -w 256 --thread-concurrency 8192
to finally get no HW errors or stales .. now i am waiting to see what the hash rate i get on the guild page before i bump it up to 14 because at 13 cgminer reports about 550 k/hs
these cards can do a lot more i am sure.
and i have another small setback .. i am not using a mining rig. i am using a dell precision t7000 series because ireally dont want to build a full mining rig atm .. and these dell precisions things will reboot the pc if it detects the gpu go over 65 degrees more than a minute .. on the bright side this pc is in a 60 degree datacenter so it is running under 60 degrees at this setting with fan adjusted to 90% using afterburner. that is with one card, i still have to put the other card into the pc. maybe i 14 will work. i guess i putting a little more work into this hopefully i get the right settings here in a few.
The missing ingredient here is probably your GPU and memory speed. Scrypt mining is *very* finicky about that. The mixture has to be *just* right else you will get a decrease in hash. Try something like GPU engine 1055 and memory 1500 or possibly 1010 and 1495.
M