# OC problem using HT - Core i7 860 P7P55D



## deadbob (Nov 17, 2010)

Core i7 860 on P7P55d 8 GB's Kingston PC3-10700 - 4 x 2

What O/C will be better performer

3.83 Ghz with Hyper threading off 
3.51 Ghz with HT on
3.30 Ghz with HT on
With HT off at 3.83 - Max temp 70-71 (within specs)
With HT on at 3.51 - Max temp 77-78 ( 5 over )not a good option - to hot
With HT on at 3.30 - Max temp 72-74

Tia Robert


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## Aus_Karlos (Mar 10, 2007)

78c is still ok (not great though) for the I7s. When it starts getting over 80c (I7 950 can sit at 85c, kill temp for all I7s is 100c) thats when you should worry.
Make sure all power saving settings are off (C1E, C3/C6/C7).
Disable Intel Turbo Boost (Normal).
You will find most the time that with HT enabled the core may become quite unstable. Tweaking the QPI/Vtt and CPU PPL voltage could correct instability with HT enabled. Only bump them up 1 notch. Never go beyond 1.86v for CPU PPL.
Whats your Vcore at? I7s are really good at OCing with barely any Vcore increase. I can get 4ghz @ 1.25v but every i7 is different as another earlier one i had sat at 1.4v.

Whats your case layout like. All the cables tied back?
Correct Airflow, Front fans suck, back fans blow, top fans blow and side fans suck?
If possible consider attaching a larger heatsink and/or fan into the north-bridge, needs to be kept below 60c for most M/B and for i7 to function properly.


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## deadbob (Nov 17, 2010)

Thanks willgive it a whirl and see what happens - YKS


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## deadbob (Nov 17, 2010)

Im running 3.8 with everything in Auto mode except for multiplier at 21 and clk at 182. Vcore is 1.25 which is on auto. Dram is auto also at 1.625 auto. Cpu PPL is auto at 1.82 If I try to raise this at all it jumps to 1.9. QPI is auto next setting is 5386.

Robert


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## linderman (May 20, 2005)

Auto settings are not really a good thing; especially on the CPU PLL; auto can overvolt your system without you knowing it; most users confuse the AUTO setting as meaning voltages are not being increased; this is NOT true. Auto increases your voltages as the motherboard sees fit; it will not factor in any safeguards, thats why manually setting things like Vdimm voltage and Cpu PLL are better; often times you can use the motherboard overclockign software (asus = auto tune gigabyte = easy tune) to establish what your target goals and limits are.

I highly suggest anyone that wants to overclock should spend a decent amount of time surfing the web to find your cpu and motherboards settings from a multitude of sources before you begin to dabble. 

"learn from the mistakes of others!"


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## deadbob (Nov 17, 2010)

Did what you said and now at 4.004 GHZ 182x22
Max TEMPS 72-74
CPU 1.25
Dram 1.675
CPU PLL 1.80
Gonna get a self contained Liquid Cooler for $80
Wow 43% o/c ON AIR
HT is off- runs 10 C hotter enabled
tKS SO MUCH

Robert


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## Aus_Karlos (Mar 10, 2007)

Dont forget to stress test, you might be able to boot to windows but as soon as you put the CPU under load you might find your system crashes and/or applications run slower than before plus memory errors.
Use Prime95 for stress testing CPU+RAM.
http://mersenneforum.org/gimps/p95v2511.zip

As a rule of thumb when OCing take it in stages dont just jump to your target, one wrong move and you'll be buying a new PC.
Most people jump the FSB up 10mhz and boot to windows, after 30-50mzh they use Prime95 and test for 6hrs or until system crash (which ever come first).
They then tweak there settings accordingly and repeat until their target OC (Most systems wont reach the users target).
Once reached they run Prime95 for 24hrs, This ensures that you have a rock solid OC with no system stability issues.
Prime95 is really important, having a solid OC will ensure minimal hardware damage to higher voltage levels, improper shutdowns and higher temperatures.


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