You are not registered yet. Please click here to register!
View Single Post - Asus P6T6 WS Revolution Info, Overclocking Guide & Photos
View Single Post
Old 30-08-2009, 11:29 AM   #51
eva2000's PC Specs
Join Date: Jul 22 2004
Location: Brisbane, Australia
Posts: 23,046 Facebook Page
Blog Entries: 42
By Booj View Post
Nice work mate

Have you tried with lower vtt? I found on air and cascade that my chip didn't like high vtt. Even at max clocks on cascade I never went over 1.48v on Gigabyte EX58 Extreme. I am running dual channel though, perhaps the vtt requirement is less.

Might be worth a try in dual channel? Pi times will take a hit, but it might help you eek out those last few mhz for 3d.
yeah dual channel may need less CPU VTT (QPI/DRAM) volts than triple channel. With my setup the high mem clocks of GT require high CPU VTT volts too otherwise don't get stable memory clocks. But will try again as well as with looser 8-9-8-22 timings to confirm if it's memory or cpu heat/clocks holding it back

By DJG View Post
It looks like BIOS 0007 has an earlier date than 0001, so I won't try it since I already tried 0001.
yup 0007 is older than 0001 bios

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

Last edited by eva2000; 30-08-2009 at 10:50 PM.
eva2000 is offline   Reply With Quote