What Sols/s rate are you getting with 290(x)? (Clocks 1030/1250)
I'm getting just about 25 Sols/s and 7950 and 280 gives about the same. (Clocks 900/1500)
By the way Miner is getting better on every release, thanks

my R9 280 at default get 29 to 37 not the X version and seem to the holdiong at 30 with this version of the miner even my r7 370 seem to run better .
Okey, thats much better than me :\
I start my miner (7950, 7950 , 280) with these options, have you changed w or i from Default?
genoil.exe -c POOL:PORT -u USER.WORKER -p z -g 0 1 2 -f 0
(E8400 and 2gigs of ram if these matter)
You can't get 30 with a Radeon 280. Not even with a 280x.