Hey there, so let me first say i got a Sapphire Vapor-X 280x.
With that being said let me tell you i'm getting aroun 700-730kh/s.
My temp is around 69C and my fan is running at around 43-45% only.
If you want to try and duplicate my results here is how i run my cgminer 3.7.2:
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
cgminer.exe --scrypt -o < MY POOL URL HERE > -u <WORKERNAME HERE> -p <PASS HERE> -I 13 -g 2 -w 256 --thread-concurrency 8193 --shaders 2048 --gpu-powertune 20 --temp-cutoff 90 --temp-overheat 85 --temp-target 71 --gpu-fan 43-100 --auto-fan --gpu-engine 1052 --gpu-memclock 1498
If you don't have the same card i suggest you play with the thread concurrency, gpu engine and gpu memclock to get the best results.
Hope this helps
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