Hmm anyone mining on 290/290x without HW errors?

--intensity 18 --thread-concurrency 56320 --gpu-threads 1 --lookup-gap 2 --worksize 64
gives me 174 kH/s for a R9 290, 1035/1250, 8gB w7 rig, catalyst 13.11 beta
UR9XyoSXCJYU639DQjBREkJTeWrcb2sRrF
You should read the whole comments following my post (2-3 pages max) to find best settings because it depends on your system RAM too.