eva2000

I think i've maxed out my first i7 920 3836A756 with 4769mhz air validation, 4652mhz 32M air, 228-230blck max air. Just swapped in my 2nd i7 920 which is an identical twin batch 3836A756 as well. Hoping 2nd one is better than first!





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
• 128MB Gainward FX5200 PCI
• 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

My i7 920 3836A756 #1 cpu with TRUE120 + Scythe Ultra Kaze 2000rpm x2 push pull in 28C room temps stock idled in bios ~33-38C. Now that I have swapped over to my 2nd i7 920 3836A756 (#2) for first time today and same cooling and room temps stock idled in bios ~28-30C temps

Seems this 2nd i7 920 3836A756 has as good a memory controller as 1st cpu. It has better CPU VTT handling as it requires noticeably less CPU VTT than 1st cpu and runs cooler under load too ~3-5C cooler. Although Prime95 isn't as good as 1st cpu. First i7 920 needed 1.232v for Prime95 @3815Mhz 4+ hrs rock stable while this second one only managed 40mins Prime95 @3815Mhz at 1.264v before system rebooted. But so far bclk wise it handles great hitting 201bclk at CPU VTT 1.21 (default) for DFI UT X58-T3EH8 board. Have yet to test for max bclk, but did a quick 32M run and it's probaby as good as 1st cpu. Fingers crossed it has a better max bclk than 228-230blck (1st cpu)

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I'm as happy as pig in mud! UPS courier dropped of a nice set of 6GB Corsair TR3X6G2000C7GTF Dominator GT triple channel DDR3 memory rated at DDR3-2000Mhz 7-8-7-20 1.65v. They're literally hot out of the oven so to speak - week 05, 2009 from label which is last week! Everest Ultimate and CPUZ SPD report week 04, 2005 which is more likely production date and week 05, 2009 is when Corsair slapped on the Dominator GT heat sinks

These Corsair Dominator GTs, are based on the new Elpida 50nmm DDR3 ICs making CAS7 a reality at DDR3-2000Mhz at only 1.65v!

Corsair sent me a typical sealed white box packaged housing blister packed individual 2GB Dominator GT modules, along with new Corsair Airflow memory cooler and a Corsair Flash Voyager Mini USB flash drive. Seems the Voyager Mini USB flash drives won't be included in retail packaging.









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
• 128MB Gainward FX5200 PCI or 512MB Inno3D 8800GT OC Edition
• 6GB (3x2GB) Corsair TR3X6G2000C7GT Dominator GT DDR3-2000Mhz 7-8-7-20 1.65v
• 80GB Hitachi 7K80 SATAII
• Pioneer DVD-RW
• 1KW Corsair HX1000 psu
• WinXP Pro SP3 full nLite updated hotfixes / Windows 7 beta dual boot

Proof that this 2nd i7 920 handles lower CPU VTT much better than 1st i7 920 cpu! First up stock DDR3-2008Mhz 7-8-7-20 testing with Windows 7 beta and Memtest Windows version running 8x instances with 590MB each.

Vdimm = 1.635v bios (1.640v DMM real)
CPU VTT = 1.440v bios (1.426v idle and 1.465v load DMM real)

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6GB Dominator GT cont...

Still testing every setting/subtiming and voltage combination to figure out what this memory can do. It's definitely true that the Elpida ICs need more Uncore volts as they clock higher for stability - more on that matter later on once I do more testing.

Just to see what's the max I could do for CPUZ Validation at 1.875v bios volts and CPU VTT ~1.63v. Ended up at DDR3-2286Mhz 7-8-7-21 1T.

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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 = 225bclk (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

Max Validation @231Bclock

CPU VTT = 1.50v





Max Screenshot @228Bclk with low CPU VTT



Max 32M @225Bclk



Max 32M @227Bclk

eva2000

Just doing some quick Super Pi 32M tests to see how this 2nd i7 920 cpu does in terms of raw cpu overclocks and to my surprise it handles like my 1st i7 920 even down to it's max Hyperthreading enabled Super Pi 32M ceiling being under 4500Mhz. On air cooling, anything over 4500Mhz will reboot part way through Super Pi 32M with HT enabled. Need to disable HT to pass Super Pi 32M at >4500Mhz speeds.

Max 32M

• @4359Mhz HT enabled at 1.456v
• @4468Mhz HT enabled at 1.488v
• @4536Mhz HT Disabled at 1.536v

Haven't pushed it higher than 1.536v vcore yet.

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Notes so far....
Just gathering some notes from brief 2nd i7 920 testing. This 2nd i7 920 3836A756 is noticeably different from my 1st i7 920 of same batch in various ways,

1. It handles way lower cpu vtt voltages needed and clocks to a higher bclk than 1st i7 920
2. But when it comes to high mem clocks >DDR3-2000Mhz and high QPI frequencies, it seems it has a more strict relationship between cpu vtt and vcore once above 1.48v cpu vtt and likes vcore to be 0.02-0.08v close to it. My first i7 920 didn't have so a strict relationship.
3. If vcore isn't as close to cpu vtt for this 2nd i7 920, then >1.48v cpu vtt will introduce slight instabilities at high mem and qpi frequency clocks. For example, inconsistent super pi 32M stability between 32M pi runs, not booting on bios save/exit after setting higher cpu vtt leaving vcore too far from cpu vtt, BSOD on windows loading and even Memtest86+ v2.11 test #2 and #3 errors and irregularities.
4. Update: Now looking back at my first overclocked screenshot on this 2nd i7 920, and the required vcore and cpu vtt voltages must of been a preview of what this cpu needed. Vcore set 1.30625v (SG = 1.32v) and CPU VTT set 1.31 (SG = 1.31).

So guys anyone have a i7 920 with such a similar relationship as my 2nd i7 920 ?

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Now that I'm testing this 2nd i7 920 3836A756, 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 (results here).

This 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

TheKarmakazi

z0mg!

I cant wait to see what you do with these George! 2 days until I can get my first kit of Elpida's (Avantium 6GB kit). I am also very interested to see what they do in dual channel on a 775 board if you have the chance!


Hopefully Corsair will be able to ship some retail units soon!