Ok to continue the fury saga.  I've got it mining. But it seems it has some weird issue when paired with any other card.  To top it off if I turn off asm it will mine with the second card and never skips a beat.  Problem is it's about 150 hashes per sec short of asm mode.  I've tried both drivers 15.12 and 16.3.2. Both have the same results. Weird thing is once it locks up and flashes the screen black hashes goto 0 on fury and a reboot will not fix it.  I have to use ddu uninstall the drivers and reinstall and it will mine again.  Asm mode will mine for exactly 7 minutes then crash.  Then I have to repeat the uninstall and reinstall the drivers.  I've tried it in two different mobos with same results.  I finally gave up and left it in by itself to see if it will mine thru the night.  After 1 hour of babysitting it I left. Figure it should continue thru the night. 460 h/s stable when I left.  I really don't understand this at all.  I've tried several versions of claymore miner back down to ver 10. Ver 10 works but what I find is odd with it is it shows the 7970 as algo 2 and the fury using algo 1. No asm in that version.  But when I run ver 12 and up it shows both cards as algo 2.  Uff sucks when ya can't figure out what is the issue. I've spent two whole days now troubleshooting. Anyone have any other trick I can try?  Would be really appreciated.  

BR
d57heinz

The best drivers i used without issues is 16.9.2 , i installed it on all of my rigs months ago and updated all rigs except one still running on 16.9.2 and it's the best performing between all rigs no problems at all.

AMD Cards available: 6
GPU #0: Ellesmere, 4096 MB available, 36 compute units
GPU #0 recognized as Radeon RX 480
GPU #1: Ellesmere, 4096 MB available, 36 compute units
GPU #1 recognized as Radeon RX 480
GPU #2: Ellesmere, 4096 MB available, 36 compute units
GPU #2 recognized as Radeon RX 480
GPU #3: Ellesmere, 4096 MB available, 36 compute units
GPU #3 recognized as Radeon RX 480
GPU #4: Ellesmere, 4096 MB available, 36 compute units
GPU #4 recognized as Radeon RX 480
GPU #5: Ellesmere, 4096 MB available, 36 compute units
GPU #5 recognized as Radeon RX 480
POOL/SOLO version

More speed is more difficult.

regarding OC a 280. my 280 only responds to core clock. at default 900 mhz it hashes about 250 sols/s and at around 1100 mhz it reaches just above 300. Memory clock have little to none impact.

Please am about to build a rig of 5x R9 270x for zecash miner

please what's the stock hashrate for R9 270x on zcash using the latest claymore miner v12.4