Post
Topic
Board Mining (Altcoins)
Re: TRULY Custom RAM Timings for GPU's with GDDR5
by
nerdralph
on 22/03/2017, 18:57:50 UTC

So I need to update MC_SEQ_MISC1, offset 54 in the hex string of the strap (offset 27 in bytes).  Are the 3 hex chars at offset 55-57 the 12 bits for MR0, or is that MR1 and MR0 is 59-61?
I know I could figure it out by comparing different straps and seeing how the bits map to the register values, but since you seem to have already figured it out...


Original Samsung 4G ( your particular GPU ) 1625
555000000000000022CC1C00CE596B44D0570F1531CB2409004AE700 [ 0B03 | 1420 ] 7A8900A003000000170F2E36922A3217

Quote
--> MC_SEQ_MISC1
 -- MR0
    WL = 3,  CL = 22,  TM = 0,  WR = 23,  BA0 = 0,  BA1 = 0,  BA2 = 0,  BA3 = 0
 -- MR1
    DS = 0,  DT = 1,  ADR = 1,  CAL = 0,  PLL = 0,  RDBI = 0,  WDBI = 0,  ABI = 0,
    RES = 0,  BA0 = 0,  BA1 = 1,  BA2 = 0,  BA3 = 0
Original Samsung 4G 1750
777000000000000022CC1C0010626C49D0571016B50BD509004AE700 [ 1405 | 1420 ] 7A8900A003000000191131399D2C3617

Quote
--> MC_SEQ_MISC1
 -- MR0
    WL = 4,  CL = 23,  TM = 0,  WR = 25,  BA0 = 0,  BA1 = 0,  BA2 = 0,  BA3 = 0
 -- MR1
    DS = 0,  DT = 1,  ADR = 1,  CAL = 0,  PLL = 0,  RDBI = 0,  WDBI = 0,  ABI = 0,
    RES = 0,  BA0 = 0,  BA1 = 1,  BA2 = 0,  BA3 = 0

I think you are off by +1 with the MR0 CAS latency.  SEQ_CAS_TIMING has CL=21(0x15) for the 1625 strap, and CL=22(0x16) for the 1750 strap.