Looking for advice tuning my 480's for XMR.

Rig:
-Gigabyte ga-970a, phenom IIx4, 4g RAM.  
-Xubuntu 16.04LTS (running from console), AMDGPU-PRO 16.60
-4x sapphire rx 480 nitro 4gb elpida, stock bios.  Stock clocks are 1143/1750

Hashrate is hovering in the mid 500's.

Settings:
- w8 g1 (haven't seen much difference going with w4 g2)
- ri currently 1088 (started at 1152, not much difference backing down as low as 1024)
- I've tried adjusting the gpu clock between 800 and 1300 and the memclock as high as 2200, and can't say any of those change a durn thing.

Had the same experience with my sapphire 470/4gb (elpida) cards.  I could occasionally get em up to 600 in windows by flogging the memclock, never got above 550 in linux until I did a memory strap (1500 copied up), and now I'm getting solid 600 on stock settings.  They run pretty hot but I think that's due to crappy reference design fan.

Not eager to flash the ROM on the 480's.  No bios switch.  Polaris bios editor doesn't work with these cards. Tempted to just live with it, in lieu of downloading a bios off the internet.  I'm open to suggestion.

By the way, these cards are on sale at Newegg for ~180.  Net of everything it was probably a decent deal, it was worth the extra 10 bucks over a 470 to get some decent fans on there.  If I can squeeze a little more out of them, it'll be a great deal.