Hello everyone! This is my first ZCash forum Post! Whoot!
Back to business...
I just recieved a new XFX RX 470 today (RX-470P4LFB6) and was stoked abotu installing it into my system, which currently houses one other RX 470 and two RX 480s. After installation, I began my Zcash mining and noticed an EXTREMELY LOW hashrate - between 50 and 60! My others are easily obtaining 280 H/s. Frustrated, I began the trouble shooting process.
Intel i5-4690k (yes, I repurposed my Hackintosh!)
32GB DDR3 RAM (See above. Yes, I know it is overkill already)
Samsung 850 EVO SSD
Four powered PCI-E Risers: 16x to 1x
1000w Bronze Power Supply
Claymore Zcash Miner v. 12.4
AMD Drivers v. 15.12 (as suggested by Claymore)
Card in Question:
XFX Rx 470 (XXX)
Part #: RX-470P4LFB6
4GB DDR5 Elpida (Micron)
I quadruple checked all wires on all components were properly plugged in to reduce the chance of potential user error. I would do so from all steps hereafter, as well.
After shutting down my system, I switched the card with my Sapphire RX 470 to rule out problems with my riser and/or power cable. After reboot I ran the Claymore miner and discovered that one card was still only able to achieve roughly 60 H/s.
Unware of which 470 was the culprit, after shutdown, I disconnected all GPUs except my Sapphire. After the reboot I started Claymore and the Sapphire achieved appropriate hashrates.
I shut down and installed only my new XFX card. After reboot and running Claymore, I identified this card was achieving hashrates extremely below that which would be expected from even a low tier binned card: 50 to 60 H/s.
I moved ther BIOS switch over under the expectation that perhaps the BIOS was either on silent, or perhaps was damaged. After reboot, it still achieved poor hashrates on Claymore.
Having the most updated drivers installed, I uninstalled all drivers and restarted. I then installed obtained the v.15.12 drivers on the official AMD repository that are suggested by Claymore. After running Claymore, the problem persisted.
Ruling our issues with my drivers, I investigated both of the VBIOS with Polaris Bios Editor. For some reason my XFX card does not have any timing for 1900. I'm not sure if this is rare or expected, but all the other VBIOS I have are STOCK with 1750, 1900, and either 2000 or 2150. Concerned that my VBIOS could be the problem, I reflashed the factory VBIOS. Both bios resulted in the same poor performance.
I then modified the VBIOS with ATI flash. No change in performance. I then modified the VBIOS with Polaris BIOS Editor and used the 1500 timing for higher timings - no change in performance. I have now reflashed to the original VBIOS that came with my card.
I am stumped. I am almost positive I just received a bunk card from Amazon. So before I return the card and deal with waiting for my return, I wanted to post on the forum in the hope that I missed something. Perhaps there is something regarding the XFX cards or Claymore that I am unaware of? I think I have exhausted all other known possibilities I have discovered in the forums. I will likely return the card Monday, so any suggestions I can try before then is much appreciated. Hopefully others who have this problem can assist or also be enlightened on the issue.