Got identical batch i7 920s = 2x i7 920 3836A756 interesting comparison especially how they handle CPU VTT and max bclk!

*** Prime95 ***

i7 920 3836A756 #1
  • @3815Mhz at 1.232v HT enabled 4+ hrs (my 24/7)
  • @4009Mhz at 1.328-1.344 HT enabled 1+ hr (my video encoding config)


i7 920 3836A756 #2
  • @3815Mhz at 1.264v HT enabled ~40mins before system reboot (didn't test further)


*** Max Super Pi 32M ***

Both cpus have similar max HT enabled 32M Pi ceiling of under 4500Mhz. HT needs to be disabled for greater than > 4500Mhz on air cooling.

i7 920 3836A756 #1


i7 920 3836A756 #2


*** Max BClock ***
Definitely this second i7 920 3836A756 is better than my first one in terms of max Bclock and low CPU VTT usage.

i7 920 3836A756 #1
  • max memtest86+ bootable bclk = 224 requiring 1.58-1.60v CPU VTT
  • max super pi 32m bclk = 222bclk (without IOH/ICH voltage tweaks) & 228bclk (with IOH/ICH voltage tweaks) requiring 1.60-1.61v CPU VTT
  • max CPUZ Validation = 230bclk requiring 1.60-1.63v CPU VTT


i7 920 3836A756 #2
  • max memtest86+ bootable bclk = 229bclk requiring 1.40-1.48v CPU VTT
  • max super pi 32m bclk = 227bclk (without IOH/ICH voltage tweaks) & ???bclk (with IOH/ICH voltage tweaks TBD) requiring 1.48-1.50v CPU VTT
  • max CPUZ Validation = 231bclk requiring 1.50v CPU VTT


TBD - Haven't tested 2nd cpu with IOH/ICH tweaks yet

System specs
  • 2x i7 920 3836A756 #1 and #2
  • Thermalright Ultra 120 Extreme + LGA1366 Bolt Thru kit + 2x 120x38mm Scythe UltraKaze 2000rpm 87cfm fans in push/pull
  • DFI LP UT X58-T3EH8 R.A51 - 01/23 beta bios
  • 1KW Corsair HX1000 psu
  • WinXP Pro SP3 full nLite updated hotfixes / Windows 7 beta dual boot