Windows 7 - Overclocking i7 860 on p7p55-M

Hey guys,

Just looking for some advice regarding overclocking.

So, heres my rig:

Antec P183 Case
Intel Core i7 860 2.8GHz Socket LGA 1156 8MB L3 Cache
Crucial 4GB (2x2GB) DDR3 1333MHz/PC3-10600 Memory Kit CL9 1.5V
Antec TruePower New 650W Modular PSU
Arctic Cooling Freezer 7 Pro rev 2 Heatpipe CPU Cooler
Asus P7P55-M P55 Socket

Currently I have a stable overclock at 3.6Ghz (3600MHz x 20), but there seems to be some sort of power saving going on, the vCore keeps dropping from 1.216 to 1.080 and the freq down to 1620MHz x 9.
Ive been searching around for power saving options such as EIST but cant find anything. Does anyone have any ideas?

Thanks,

Max

EDIT-Update:

Okay so the searching I did around the internet turned up several power saving options in the BIOS. I have these all disabled (including intel speedstep). A few of the options people say to turn off just vanish when I switch to manual overclocking, so I am assuming that these are automatically disabled. The other reason I feel safe assuming this is because it has only started doing this on newer bios updates, in the older versions the options were still there.
In this motherboard you cant specify your VCore voltage, you can only set the VCore over voltage. Now I read that this was the extra voltage over 1.0v. Its currently set at 0.2v. However I've noticed that when I open up CPU-Z, whether under stress testing or not the voltage seems to fluctuate. I have tried enabling and disabling certain voltages but just cant seem to get it to stop this drop. Max temps on Coretemp and Real Temp are ~72 Celcius.
When the voltage drops, the bus speed stays the same, but the multiple drops to 9, making the speed 1620.0MHz..... It seems to spend more time at the 9 multiplier than at 20...
If anyone has any ideas please enlighten me!

Update 2
I thought about playing with prime95 when not over clocked and a strange thing happened. The processor runs at 133.8 x 22 = 2.943GHz @ 1.128v, but when you activate the torture test the voltage drops to 1.072v...now i really have no idea whats going on. I activated intel turbo boost and another feature for allowing the OS to control the freq. of the CPU, but why would the voltage drop? Also why is nothing else changing?

I just played around with an 860 on an EVGA board. I did not spend too much time with it but I found on that chip it was happy till 3.6 and then the temps went too high. He had a nice cooler Zalman 9700 I think. Hit almost 99C with prime 95. Backed it down to 3.5Ghz and it was happy running at 62C full load.
I can’t believe that chip tops out at 3.5 but I did not have all weekend and that is sometimes how long it takes to find the happy spot on the CPU.

Personally I have had great success with my 920 CPU stock 2.6 running everyday at 3.850.
The voltage is the key along with temps. If you run faster you need more power, more power more heat.
Properly installing the heat sink and fan can make a big difference too. What are your temps (speedfan, core temp)
PS.
Turbo mode can be turned off in the bios.
You may need a bigger power supply.
Try 1.3 – 1.4 Volts on the Vcore and see how far it goes with the temps.
Have a look here > Guide to Overclocking the Core I7 860 to 4.0GHz on a Evga P55 FTW 200 - Overclock.net - Overclocking.net

Hey thanks for the reply!

Well I found the weird setting that was making my multiplier drop, it was something called CPU TM functions, although the bios just muttered something about spare cycles....hmmm glad i found it though.

You may be right about my PSU. I was running stable for 10 mins (not long i know) at 3.8GHz, temps were about 80 Celsius (too high i know), but then the computer just turned off! Does this sound like a power issue to you? Im now playing around with 3.6GHz, although im not terribly sure what I'm doing. I have most things set to auto and was just playing around with VCore. When you start introducing other variables, (ICM, VTT, DRAM etc...) how are supposed to know which one to change when you encounter an error?

Thanks for the link, reading now. Seems to be about the only thread I havnt scoured so thanks!

Max

Okay new post to draw attention away from all the info above for those who cant be bothered to read it all...!
My Problem:

I am overclocking, no errore in prime95 and temps not going over ~70 or ~80 (3.6GHZ and 3.8GHz respectively) when suddenly the computer just switches off, any ideas?

I am only adjusting the bus speed, the multiplier and the vCore over voltage, everything else is on auto.

Thanks,

Max

It is common and by design that the core voltage will drop under load. It is called droop and is designated by Vdroop.

Your CPU will power off if it gets too hot, but that threshold is well above 80c. It probably was unstable and crashed.

What are your overclock Voltage settings. It would help to know everything you have changed.

Intel TurboBoost is what allows it to be overclocked (and indeed run at full speed), so make sure that isn't turned off (might be SpeedStep for you).

Sounds like you really need a better cooler on that CPU, 80C is a tad high for that low of an overclock.

~Lordbob

Hi, thanks for the replies.

@GeneO, I have been playing around with all the settings, but even after a days worth of reading I was still left unsure which ones I should be changing. I saw a thread with positive results on my motherboard where they only changed the vCore over voltage, however other threads changed the ICM, DRAM and PLL too.

Here are the screenshots of my bios, these are all the overclocking settings I have access to.
(See attached)

@Lordbob75
The turbo function disappear when set 'AI Overclock Tuner' to 'Manual'. This setting is required in order to access any frequency and voltage settings.
If you look at screenshot 3, you can see a setting called C1E Support, CPU TM Function and C-STATE Tech; I read to turn these off for a more stable overclock. These are the settings I was having trouble with in my first post relating to the multiplier drop. Are these the settings you could be referring to?

turboboost isn't required to overclock. turboboost will automatically overclock one core when others are idle. In fact, if you want to overclock all cores, you should usually turn it off or it may boost one of the overclocked cores beyond what you expected when the others are idle, and your system will become unstable. That is probably why the MB disables it when it is overclocked.

I wouldn't turn off Intel TM function. It should only affect your performance if the processor is way overheating to protect your processor. It may turn C1E on, which will lower frequency on a core when it is idle. This also doesn't affect performance but does power and temps so I leave it on. Besides that I see you have only bumped up Vcore which is good.

You have moderately overclocked so it is probably stable with just the increase in Vcore. Going higher, you may need to change the IMC and other voltages, but read up a lot first or you can get into trouble.

When you say stable and quote a load temperature, how are you arriving at that? You should run Prime95 torture test with a large custom FFT size and with using about 75% of your memory and with round -off checking enabled for at least half a day without errors or crashing before you can call it stable. And your need to monitor the temperature. If you want this to be a 24x7 overclock, your temperatures while running Prime95 this should not exceed 72c in my opinion. If it does then you need better cooling.

I recall my motherboard and chipset (sandybridge) requiring TurboBoost in order to run the CPU at full speed at all. I might be wrong though and I don't have my desktop to check at the moment.

~Lordbob