So I recently bought a new Gigabite Radeon R9 270 for around $230. With proper config, I reached 450 kH/s.
"setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS=1
cgminer --scrypt -o xxx -u xxx -p xxx -I 19 -g 1 -w 512 --thread-concurrency 15232 --temp-target 63 --temp-cutoff 85 --lookup-gap 2 --gpu-memdiff 0"
My question is, should I believe my cgminer or pool stats with kH/s?
Your cgminer will have a more accurate representation of what you are mining at. You would be able to obtain more kh's with intensity on 20 but you would have to change other settings to accommodate it so no HW errors occur.