Took a side by side screenshot of my 12x mem multi DDR3-2184Mhz 7-8-7-20 1T 32M run versus my 10x mem multi higher cpu clocked DDR3-2118Mhz 7-8-7-20 1T 32M run to see what cputweaker reported for my subtimings. See if any subtiming settings are a factor.



DDR3-2184Mhz (12x mem) vs DDR3-2118Mhz (10x mem)

  • QPI/DRAM volts = 1.55v vs 1.6375v due to lower bclk needed on 12x mem config
  • tRFC = 110 vs 88 could be a factor ?
  • tRRD = 7 vs 7 both same
  • tREFI = 955 vs 849
  • tFAW = 37 vs 33
  • tRTL A channel = 56 vs 57
  • tWTP = 27 vs 26
  • tRTP = 7 vs 6
  • Write to Read (same rank) = 20 vs 19


Going to play with subtimings and see

Update: Dropped cpu multiplier to 19x and using 10x memory multiplier, will try to reproduce similar looser subtimings as used in my DDR3-2184Mhz 7-8-7-20 1T run with 12x memory multiplier. I managed to get as far as Super Pi 32M stable @DDR3-2188Mhz 7-8-7-20 1T at 1.84v vdimm

Manually set following subtiming values in bios:
  • tRFC = 110
  • tFAW = 37
  • Back to Back CAS# Delay = 4 (tightened to try and offset loosened tRFC value)
  • Write to Read (same rank) = 20


Super Pi 32M passed at:


DDR3-2158Mhz 7-8-7-20 1T at 1.72v



DDR3-2167Mhz 7-8-7-20 1T at 1.78v



DDR3-2177Mhz 7-8-7-20 1T at 1.80v



DDR3-2188Mhz 7-8-7-20 1T at 1.84v