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Topic: 24+ Mh R9 380, looking for Tonga power control (Read 765 times)

sr. member
Activity: 588
Merit: 251
September 16, 2016, 10:50:52 PM
#1
I've seen a couple posts about tweaked R9 380 ROMs, but until recently, nobody has provided details of how they were doing the mods.  Thanks to a discussion on /r/ethermining, I've figured out how to modify the RAM timing.  I've been playing with cards using Elpida W4032BABG-60-F and H5GC4H24AJR-T2C, and with both RAM types I've been able to overclock the RAM to 1675 stable which gives just over 24Mh with the core running at 910Mhz.  I'm now working on a single BIOS image that should work on all R9 380 cards that use the NCP81022 VRM, with Elpida or Hynix RAM.

I've also been experimenting with undervolting, but so far have not figured out how to change the dynamic power (EVV) voltages.  I can set fixed core voltages for each DPM state, but I can't figure out how to set a base DPM0 voltage and have the rest of the offsets based on the leakage characteristics.  I also haven't figured out how the two Tonga voltage tables impact VDDCI.  Has anyone figured out Tonga power control?


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