eva2000

System specs

• Intel Core i7 920 3836A756
• Thermalright Ultra 120 Extreme + LGA1366 Bolt Thru kit
• DFI LP UT X58-T3EH8 R.A51
• HIS HD4870x2 stock hsf
• 2x1GB Corsair DDR3-2133C9DF + 1GB G.Skill PC3-12800HZ
• 750GB Samsung HD753LJ
• Pioneer DVD-RW
• 1KW Corsair HX1000 psu
• WinXP Pro SP3 nLite fully updated

Mixed 2x1GB Corsair DDR3-2133C9DF Dominator Samsung HCF0 modules + 1GB G.Skill PC3-12800HZ Samsung 816 HCF0 module together for first time Samsung HCF0 based triple channel configuration. The G.Skills are holding back the clocks as they need around ~0.1-0.15v more vdimm at same clocks as Corsair 2133 stuff, but still managed to be Super Pi 32M stable @DDR3-2191Mhz at 1.965v bios set vdimm.

@DDR3-2191Mhz at 1.965v

Don't mind the slow PI time as just testing how far I can clock this mixed set of 3x1GB Samsung HCF0 modules

CPUZ Validation @DDR3-2211Mhz at 1.965v

Still at 1.965v vdimm set in bios so probably limited by max Bclk.

eva2000

@DDR3-2076Mhz 8-8-8-20 at 2.025v

eva2000

Max BCLK with 10x Memory Multiplier
- limited by memory max overclock frequency

Now to try max Bclk frequency with 10x memory multiplier - ultimately will be limited by how far my memory modules can overclock

System specs

• Intel Core i7 920 3836A756
• 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 - 01/06 beta bios
• 128MB Gainward FX5200 PCI
• 2x1GB Corsair DDR3-2133C9DF Dominator + 1GB G.Skill PC3-12800HZ (3x Samsung HCF0)
• Ram cooling: 3x 60x25mm Sunon 23.5cfm Maglev fans
• 80GB Hitachi 7K80 SATAII
• Pioneer DVD-RW
• 1KW Corsair HX1000 psu
• WinXP Pro SP3 full nLite updated hotfixes / Windows 7 beta dual boot

Interesting that up to DDR3-2263Mhz system registered 3x1GB Samsung HCF0 unmatched modules as triple channel, but when I hit DDR3-2298Mhz, windows reported dual channel instead of triple channel ?? Not enough volts somewhere or maybe my 1GB G.Skill PC3-12800HZ module can't keep up with my Corsair DDR3-2133C9DF modules ??

Triple Channel CPUZ Validation @226Bclk
+
DDR3-2263Mhz at 1.995v bios vdimm

QPI Bus frequency = 4074Mhz

DDR3-2298Mhz at 2.025v vdimm bios
Triple channel showing up as Dual channel

Max Super Pi 32M @DDR3-2228Mhz 1.995v vdimm bios

eva2000

Flashed to 01/23 pre-beta bios and seems 6x mem multiplier runs alot better than before. Prior max mem clock with 6x mem was around 1049mhz 9-9-9-25 regardless of volts. Now with same memory can hit 1104mhz 8-9-8-22 for 32M pi and 1123mhz 8-9-8-22 for validation all at 2.025v bios with 6x mem multiplier

CPUZ Validation
@DDR3-2247Mhz 8-9-8-22 at 2.025v bios

Super Pi 32M
@DDR3-2208Mhz 8-9-8-22 at 2.025v bios

Best 32M Pi effiency I've managed to date = 3864.4 x 550.891 seconds = 2128863

eva2000

Now that I'm testing my 2nd i7 920 3836A756 which differs from the i7 920 used for above memory clocks, I thought I'd revisit this mismatched Samsung HCF0 based 3x1GB configuration to see how well this 2nd i7 920 3836A756 cpu clocks memory compared to 1st i7 920.

Second i7 920 doesn't disappoint, resulting in a higher max Super Pi 32M stable memory clock of DDR3-2237Mhz 9-9-9-24 1T but at slightly higher volts. CPUZ Validation is higher if you only count the validation which reported 3x1GB modules as triple channel at DDR3-2283Mhz 9-9-9-24 1T vs DDR3-2263Mhz 9-9-9-24 1T. If you count validation of 3x1GB which reported as dual channel due to lack of volts then 1st i7 920 still comes out on top at DDR3-2298Mhz 9-9-9-24 1T.

i7 920 3836A756 #1

• Max Super Pi 32M = DDR2-2228Mhz at 1.995v vdimm (CPU VTT 1.61v)
• Max CPUZ Validation = DDR3-2263Mhz at 1.995v (CPU VTT 1.61v)
• Max CPUZ Validation (but cpuz reported as dual channel) = DDR3-2298Mhz at 2.025v bios (CPU VTT 1.61v) **

** Most likely due to inadequate volts leading to dual channel being reported instead of triple channel)

i7 920 3836A756 #2

• Max Super Pi 32M = DDR2-2237Mhz at 2.01v vdimm (CPU VTT 1.63v)
• Max CPUZ Validation = DDR3-2283Mhz at 2.01v (CPU VTT 1.63v)

DDR3-2283Mhz 9-9-9-24 1T

Super Pi 32M @ DDR3-2237Mhz 9-9-9-24 1T

Super Pi 32M / Everest 4.60.1635 Beta



Super Pi 32M / Everest 5.00.1652 Beta



System specs

• Intel Core i7 920 3836A756 #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
• 512MB Inno3D 8800GT OC Edition
• 2x1GB Corsair DDR3-2133C9DF Dominator + 1GB G.Skill PC3-12800HZ (3x Samsung HCF0)
• Ram cooling: 3x 60x25mm Sunon 23.5cfm Maglev fans
• 750GB Samsung SATAII
• Pioneer DVD-RW
• 1KW Corsair HX1000 psu
• WinXP Pro SP3 full nLite updated hotfixes / Windows 7 beta dual boot