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]

 

[wazza300]

leave hyperthreading enabled,it uses 8 cores 4 real/4 virtual rather than 4 real cores with hyperthreading turned off

more cores=more performance

I used to use cpu offset +0.0750v for overclocking @ 4.2ghz can try same for 3.8ghz,enable all power saving

 

[Five.Stars]

I believe this is merely down to HT requiring ever so slightly higher voltages to maintain the same frequencies on a stable basis.

 

[darrenkarp]

I have the exact same processor sat in a GB EX58-UD3R mobo and even at 1.30625v I'm having the occasional BSOD x101 code (more vcore voltage needed) when flying with Microsoft FSX. Those vcore volts above look way too low. What am I missing here?

 

[wazza300]

it depends on each chip,some need around the 1.35v mark some need less than 1.3v

best one I had used 1.23v for 4.2ghz

 

[darrenkarp]

Perhaps the BSOD code is wrong?

 

[wazza300]

101 is cpu v,and 124 is qpi/vtt on x58

you need a really good cooler then you can add more voltage,anything below 1.4v is ok

 

[darrenkarp]

Got me an H100i now but think I've played around too much with the BIOS settings trying to get to 3.6 , 3.8...now need an expert!

 

[wazza300]

here's the bsod code list

http://forums.tweaktown.com/gigabyte/43058-bsod-error-codes.html

where are you at with qpi/vtt and cpu v? I only used to change a few settings the rest were fine on enabled/auto

 

[darrenkarp]

I've reset everything to optimised defaults now as I seem to be going backwards and not forwards in my attempt to get a stable 3.8 or higher OC.

 

[wazza300]

what cpu voltage is used in the bios ? whatever amount it is once you set it to normal

add extra that's needed in dvid,so say its showing 1.2v and you need 1.25v to be stable then set dvid to +0.05000v = 1.25v and so on

try 3.6ghz

20x 181 bclk (turn off intel turbo boost so it stops it boosting to 21x)
8x mem multi
16x uncore freq

qpi/vtt 1.34v
cpu v normal
dvid try with +0.0850v

that's all you need to change to overclock tbh,main voltages are qpi/vtt and cpu voltage/dvid to tweak later to get stable

 

[darrenkarp]

is there any software out there that can read my BIOS settings once I've booted into Windows?

 

[wazza300]

yh gigabytes own easytune,dont use it to overclock with though as it will add waay more voltage then needed

just use it to monitor voltages

 

[darrenkarp]

ok. give me the list of settings for 3.6 along with what tests I need to perform to establish its stable if you can.

 

[wazza300]

would help if you knew the cpu voltage when set to normal in bios,then I can give you a more accurate dvid to try

but this should be all you need to do for 3.6ghz

20x 181 bclk (turn off intel turbo boost so it stops it boosting to 21x)
8x mem multi
16x uncore freq

qpi/vtt 1.34v
cpu v normal
dvid try with +0.0850v (this depends on how much default cpu v)

test with prime95 blend test,and or 5 runs intel burn test,if it passes those your pretty stable imo

 

[darrenkarp]

how long do I run p95 for?

 

[wazza300]

3 to 4 hours

or do short 5 runs intel burn test,then test in normal usage/gameplay ect

 

[darrenkarp]

hitting low 80's with P95 after 60 seconds or so with the H100i on performance (max) mode!

 

[darrenkarp]

now high 80's!

 

[darrenkarp]

something's not right.