Overclocking with or without HyperThreading: Wut?

[Draeger]

Been having a look online for some guides on achieving a reasonable and safe o/c of about 3.8Ghz with low voltage settings on an i7 920 D0 sat on an Asus P6X58D-E.

I found THIS thread on a forum which has a ton of info in there. However, the settings which are listed for the desired overclock of 3.8 show 'With HyperThreading' and 'Without HyperThreading'. Can someone explain what the difference is? Here are the settings listed for 3.8 Ghz:-

***************************************
Running 3.80GHz w/o HyperThreading (Stable)
***************************************

Code:
Ai Overclock Tuner.....................[Manual]
CPU Ratio Setting......................[21.0]
Intel(r) SpeedStep(tm) Tech............[Disabled]
Xtreme Phase Full Power Mode...........[Enabled]
BCLK Frequency.........................[181]
PCIE Frequency.........................[100]
DRAM Frequency.........................[DDR3-1451MHz]
UCLK Frequency.........................[2903MHz]
QPI Link Data Rate.....................[Auto]

CPU Voltage Control....................[Manual]
CPU Voltage............................[1.15625]
CPU PLL Voltage........................[1.80]
QPI/DRAM Core Voltage..................[1.20000]
IOH Voltage............................[1.12]
IOH PCIE Voltage.......................[1.50]
ICH Voltage............................[1.20]
ICH PCIE Voltage.......................[1.50]
DRAM Bus Voltage.......................[1.64]
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]
CPU Differential Amplitude.............[800mV]
CPU Clock Skew.........................[Delay 300ps]
CPU Spread Spectrum....................[Disabled]
IOH Clock Skew.........................[Auto]
PCIE Spread Spectrum...................[Disabled]

C1E Support............................[Disabled]
Hardware Prefetcher....................[Enabled]
Adjacent Cache Line Prefetch...........[Enabled]
Intel(r) Virtualization Tech...........[Disabled]
CPU TM Function........................[Enabled]
Execute Disable Bit....................[Enabled]
Intel(r) HT Technology.................[Disabled]
Active Processor Cores.................[All]
A20M...................................[Disabled]
Intel(r) SpeedStep(tm) Tech............[Disabled]
Intel(r) C-STATE Tech..................[Disabled]

**************************************
Running 3.80GHz w/ HyperThreading (Stable)
**************************************

Code:
Ai Overclock Tuner.....................[Manual]
CPU Ratio Setting......................[21.0]
Intel(r) SpeedStep(tm) Tech............[Disabled]
Xtreme Phase Full Power Mode...........[Enabled]
BCLK Frequency.........................[181]
PCIE Frequency.........................[100]
DRAM Frequency.........................[DDR3-1451MHz]
UCLK Frequency.........................[2903MHz]
QPI Link Data Rate.....................[Auto]

CPU Voltage Control....................[Manual]
CPU Voltage............................[1.16875]
CPU PLL Voltage........................[1.80]
QPI/DRAM Core Voltage..................[1.20000]
IOH Voltage............................[1.14]
IOH PCIE Voltage.......................[1.50]
ICH Voltage............................[1.20]
ICH PCIE Voltage.......................[1.50]
DRAM Bus Voltage.......................[1.64]
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]
CPU Differential Amplitude.............[800mV]
CPU Clock Skew.........................[Delay 300ps]
CPU Spread Spectrum....................[Disabled]
IOH Clock Skew.........................[Auto]
PCIE Spread Spectrum...................[Disabled]

C1E Support............................[Disabled]
Hardware Prefetcher....................[Enabled]
Adjacent Cache Line Prefetch...........[Enabled]
Intel(r) Virtualization Tech...........[Disabled]
CPU TM Function........................[Enabled]
Execute Disable Bit....................[Enabled]
Intel(r) HT Technology.................[Enabled]
Active Processor Cores.................[All]
A20M...................................[Disabled]
Intel(r) SpeedStep(tm) Tech............[Disabled]
Intel(r) C-STATE Tech..................[Disabled]

 

[Draeger]

enable all power saving

By this, what do you mean? Stuff like Speedstep etc?

My P6X58D-E board won't arrive until next week so I've not had a chance to look around in the BIOS as yet but will more than likely resurrect this thread in a few days time to pop a few more questions.

 

[Draeger]

Use CPU offset to add extra voltage so that CPU downclocks at idle

Dumb question - Is that a BIOS setting?

 

[Draeger]

A bit stumped

Right - Finally managed to put this system together so I'm back to pester you folks 'in the know' with a few questions. First one up is DRAM timings and voltages. I'm running Corsair XMS3 1600 sticks, 3 of 2Gb each, all sat in the blue slots on the mobo. The timings on these are 7-7-7-20 at 1.65v. I've had a shifty in the BIOS to see if I could quickly change these before I start tweaking anything else but I'm a bit confused as to what values to change to 7-7-7-20. I'm not a complete idiot (I hope) but the DRAM options in this BIOS on this board look vastly more complex than my old P5K. There seem to be a lot more options in there at first glance. So what do I basically need to change at this point to get the XMS3 running at 7-7-7-20 @ 1.65v?

Ta.

 

[Draeger]

Roger that, I'll go and do that just now. What about DRAM Frequency? Set to 1600 I assume? This is what CPU-Z is saying its all sat at just now on Auto:-

 

[Draeger]

Okeydoke, timings changed to 7-7-7-20. Do these screens of CPU-Z look ok? I tried changing the DRAM Bus voltage and it threw a warning at me, is it ok to go ahead and change it to 1.65v anyway? As you can see from the second CPU-Z screenshot on Auto its giving 1.50v to three of the RAM sticks and 1.65v to the last one. Leave it at that or manually adjust to 1.65v? Last image shows the warning that popped up in the BIOS:-

 

[Draeger]

Cool. I increased the BCLK to 150 (other than the DRAM timings and freq that's the only thing I've changed within the BIOS) and it's now sitting at 3148.14MHz. But it seems to have set the DRAM frequency down a little from what it was @801.3 MHz to 749.9MHz :-

 

[Draeger]

yeah that's right,ram freq is linked to the bclk so if you raise/lower it it will raise/lower the ram speed

EDIT: 150 bclk x 10x memory multi = 1500mhz ram speed and so on

Ta.

In that case, I'll bung it up to 160, I assume that as well as upping the CPU speed that doing so will bring the RAM speed back up to 1600? I've ran Prime for an hour and a half with no issues at the BCLK of 150 so 160 is worth a shot I reckon. Ideally I'm after a mild overclock with no additional voltage increase, certainly at this stage of the game anyway.

 

[Draeger]

Cheers, I'll go give it a shot. Temps running Prime are hovering around the 60-65 deg C level, that sound about right? HSF is a Coolermaster Hyper 612S set up with push/pull 120mm fans - the 'front' fan is the original fan which came with it, the rear fan is a Coolermaster Sickleflow 120mm. It's all sat in a Zalman Z3 Plus case which has good airflow through it with 2 x 120mm fans up front, 1 x rear and 2 x top mounted 120mm fans.

 

[Draeger]

Right, rebooted after changing to 160 BCLK and its sat here now:-

Should Speedstep and Turbo Mode be left on or disabled? I'll run Prime for a bit and see how it goes.