Experienced OCers: help me optimize my overclock (i7 920 + P6T Deluxe)

[Imyourzero]

I very rarely visit this subforum, but I decided it was time to ask you guys for some help.

I've been running my sig rig for well over a year now, and at one point I decided to try my hand at overclocking. Overclocking on the X58 chipset seemed a lot more complex than on my previous Socket 775 setup, but I know most of those new settings have been figured out by now. At the time, I just searched for P6T overclocking guides to see what those guys were doing, but there were a ton of settings that were never really explained and while I eventually reached an overclock of ~3.7 GHz, I never really felt like I understood everything.

I updated to a newer BIOS a few months back and have been running stock clocks ever since, because I wanted to try to beat my previous overclock and do it right. I would like to ask for some assistance this time because I know there is a lot of experience in this forum and I'm fairly new to overclocking (my first experience with it was when I got my C2D E6600 and P5B Deluxe, and my first computer was a 486 DX2 66 MHz back in 1996 or so).

Before I reset my mobo back to the default values, I wrote down the values that I had been using. I'd like you guys to take a look at those and see what I could have/should have done differently, and I'd like to start at step 1 and get this baby as close to 4 GHz as we can. It's the earlier i7 chip (C0? The newer ones are D0, right?) and as much as I'd love to get to 4 GHz, if we can't safely do so then I'll be happy with the overclock that I had previously. The system was very stable with the settings I'm about to list. Stability and a safe overclock are priority #1; I'm not interested in a bleeding-edge overclock.

Relative system components:

i7 920 - C0 stepping
TRUE with push fan
6GB Corsair Dominator DDR3-1600 8/8/8/24
6GB Corsair XMS3 DDR3-1600 8/8/8/24


Previous BIOS settings:

Ai Tweaker
Ai Overclock Tuner: Manual
CPU Ratio Setting: Auto
Intel Speedstep Tech: Disabled
BCLK Frequency: 175
PCIE Frequency: 100
DRAM Frequency: DDR3-1403
UCLK Frequency: 2807 MHz
QPI Link Data Rate: Auto

DRAM Timing Control: 9-9-9-24-5-74-11-7-25-0 (All auto)
CPU Voltage: 1.25000
CPU PLL Voltage: 1.80
QPI/DRAM Core Voltage: 1.25000
IOH Voltage: Auto
IOH PCIE Voltage: Auto
ICH Voltage: Auto
ICH PCIE Voltage: Auto
DRAM Bus Voltage: 1.64

Load Line Calibration: Auto
CPU Differential Amplitude: Auto
CPU Clock Skew: Auto
CPU Spread Spectrum: Disabled
IOH Clock Skew: Auto
PCIE Spread Spectrum: Auto

Advanced
__CPU Configuration__
CPU Ratio Setting: Auto
C1E Support: Enabled
Hardware Prefether: Enabled
Adjacent Cache Line Prefetch: Enabled
Intel Virtualization Tech: Enabled
CPU TM Function: Enabled
Execute Disable Bit: Enabled
Intel HT Technology: Enabled
Active Processor Cores: All
A20M: Disabled
Intel Speedstep Tech: Disabled
Intel C-State Tech: Disabled

__Chipset__
North Bridge Configuration
PCI Express Selector: Auto

Intel VT-d Configuration
Intel VT-D: Disabled

If there are any more settings that are relevant that I need to post, please list them and I'll include them.

I do have a few initial questions, and might have a few more during the course of this thread (if it gets any replies, lol). Should I be using memory profiles, or is manual the way to go? What's the maximum safe voltage for a long term overclock? I was never able to achieve much more than a BCLK of 175 with the above setup, but I wanted to keep CPU voltage as close to stock as I could to minimize heat and CPU degradation.

So - where to start?

 

[Thor86]

Hey there,

C0 revision 920s are pretty limited to around 3.6 maybe 3.8Ghz overclocks with decent air flow/cooling.

For memory profiles, I would advise not using them, and use manual for everything.

Maximum safe oc voltages for cpu I would keep it under 1.4vcore. As for memory, under 1.65vmem, and the vtt should be no more than .5 difference from vmem regardless, or you risk frying your cpu/mc.

if you want to try for higher BLCKs, then I suggest you try and disable Hyper-threading if you do not need 8 logical cpus.

I'll get back to you with my bios settings and version as well.

 

[Soccerman06]

I have a C0 and the most your looking at is 3.8 ghz without serious voltage, I'm maybe at 60c at load but can't go any higher, ie voltage requirements. I'm sitting at 1.41v and would rather not go any higher.

 

[Imyourzero]

Thanks for replying, guys. Bit-Tech was able to hit 4.0 GHz with 1.3v with theirs, but maybe they got a cherry-picked C0. I thought I might have some more headroom since I attained 3.7 GHz so easily with 1.25v, but really any gains after that are going to be negligible so I'll likely just set everything back to how it was. I got the 3.7 GHz with the 6GB Dominators, and I'm wondering if I'll have to dial some settings down now that I have all six DIMM slots filled.

Thor86, if you could post your settings I'd appreciate it since I have no idea what some of those settings are and what they should be set to. Namely the IOH stuff, A20M, C1E support, etc. I've always heard that spread spectrum should be disabled when overclocking, and to be honest I have no idea what it's for anyway.

 

[Thor86]

Bios Settings

Ai Tweaker
Ai Overclock Tuner [Manual / Default-Auto]
CPU Ratio Setting [21.0 / Default-Auto]
Intel SpeedStep Tech [Disabled / Default-Enabled]
Intel Turbo Mode Tech [Disabled / Default-Enabled]
BLCK Freqency [200 / Default-Auto]
PCIE Frequency [100]
DRAM Frequency [DDR3-1603MHz / Default-Auto]
UCLK Frequency [3208MHz / Default-Auto]
QPI Frequency [7218MHz / Default-Auto]

CPU Voltage [1.275 / Default-Auto]
CPU PLL Voltage [Auto / Default-Auto]
QPI/DRAM Core Voltage [1.275 / Default-Auto]
IOH Voltage [Auto]
IOH PCIE Voltage [Auto]
ICH Voltage [Auto]
ICH PCIE Voltage [Auto]
DRAM Bus Voltage [1.64 / Default-Auto]
DRAM DATA REF Voltage on CHA [Auto]
DRAM CTRL REF Voltage on CHA [Auto]
DRAM DATA REF Voltage on CHB [Auto]
DRAM CTRL REF Voltage on CHB [Auto]
DRAM DATA REF Voltage on CHC [Auto]
DRAM CTRL REF Voltage on CHC [Auto]
Load-Line Calibration [Enabled / Default-Auto]
CPU Differential Amplitude [Auto]
CPU Clock Skew [Auto]
CPU Spread Spectrum [Disabled / Default-Auto]
IOH Clock Skew [Auto]
PCIE Spread Spectrum [Disabled / Default-Auto]

Dram Timing Control
1st Information: 7-7-7-20-6-88-14-8-30-0
CAS# Latency [7]
RAS# to CAS# Delay [7]
RAS# PRE Time [7]
RAS# ACT Time [20]
RAS# to RAS# Delay [Auto]
REF Cycle Time [Auto]
WRITE Recovery Time [Auto]
READ to PRE Time [Auto]
FOUR ACT WIN Time [Auto]
WRITE to READ Delay [Auto]
2nd Information: 1N-50-52-54
Timing Mode [1N]
Round Trip Latency on CHA [Auto]
Round Trip Latency on CHB [Auto]
Round Trip Latency on CHC [Auto]
3rd Information: 8-8-18-8-8-8-7-6-4-7-7-4
WRITE to READ Delay (DR) [Auto]
WRITE to READ Delay (SR) [Auto]
READ to WRITE Delay (DD) [Auto]
READ to WRITE Delay (DR) [Auto]
READ to WRITE Delay (SR) [Auto]
READ to READ Delay (DD) [Auto]
READ to READ Delay (DR) [Auto]
READ to READ Delay (SR) [Auto]
WRITE to WRITE Delay (DD) [Auto]
WRITE to WRITE Delay (DR) [Auto]
WRITE to WRITE Delay (SR) [Auto]

Advanced
CPU Configuration
CPU Ratio Setting [20 / Default-Auto]
C1E Support [Disabled / Default-Enabled]
Hardware Prefetcher [Enabled]
Adjacent Cache Line Prefetch [Disabled / Default-Enabled]
Intel Virtualization Tech [Enabled]
CPU TM Function [Disabled / Default-Enabled]
Execute Disable Bit [Enabled]
Intel HT Technology [Disabled / Default-Enabled]
Active Core Processors [All]
A20M [Disabled]
Intel SpeedStep Tech [Disabled / Default-Enabled]
Intel Turbo Mode Tech [Disabled / Default-Enabled]
Intel C-STATE Tech [Disabled]

Power
ACPI 2.0 [Enabled]

 

[Imyourzero]

Thanks dude. What RAM do you have?