These are my settings using lasybear's X11 mod kernel. I beleive the cards can be pushed a little harder, but I have no HW errors with these.
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I copied and pasted your 270X settings into a bat file and the most I could get was 1.3mh/s. I have Asus and PowerColor cards. Have no idea why my hashrate is so much lower with the same settings.

Try my settings (I'm using LTCRabbit mod):
setx GPU_MAX_ALLOC_PERCENT 100
setx GPU_USE_SYNC_OBJECTS 1
.\sgminer\sgminer.exe -k x11mod -o stratum+tcp://stratum.cryptotrain.net:4444 -u UTCAddress -p 1234 -I 16 -w 256 --thread-concurrency 8193 -g 2 --shaders 1280 --gpu-engine 1100 --gpu-memclock 1400
I got it going. Didn't have things set up right in CG watcher. Getting 2.1mh/s now. Up from the 1.8mh/s I was getting. Thanks to all for posting settings.