Core i7 860 OC and Heat

[yolt]

I've been working on getting my i7 860 to the highest OC, but I want to make sure my temps are in spec. I sit at about 27 degrees idle for the highest temp core and 65-66 full load when running prime95. I'm currently running at 3.46ghz and had to bump the CPU voltage to 1.35. My question is what should I be looking at for max idle/load temps for this chip? Is there a limit on what vcore voltage I should be using? Any insight would be greatly appreciated!

 

[CurseTheSky]

Generally anything under 80c load (Linpack and similar high-stress tests) should be fine. Personally, I try to keep mine under 70c, and even 60c if possible.

 

[RussianSensation]

1.35V at 3.46ghz seems way too high. 3.5ghz should be doable at stock. Did you increase your QPI/VTT voltage? Did you try booting at 1.30V at 3.5ghz?

Are you running your DDR3 at 1.65V or below?

What is your cooler of choice?

 

[yolt]

Originally posted by: RussianSensation
1.35V at 3.46ghz seems way too high. 3.5ghz should be doable at stock. Did you increase your QPI/VTT voltage? Did you try booting at 1.30V at 3.5ghz?

Are you running your DDR3 at 1.65V or below?

What is your cooler of choice?

Thank you both for your responses. In regards to your questions, I haven't touched my QPI/VTT at all. I did try booting at 1.30V at 3.5GHz, but keep in mind I am still using the "turbo" mode, so my OC threshold will probably be around 3.5GHz (as it would be up around 4GHz if only one core is being utliized). I haven't attempted any OC without turbo, as I like the idea of not having all 4 cores run if they don't need to and increasing the speed of one core if the application I'm running only calls for one or two cores. How do you recommend I go about tweaking the QPI/VTT? Both are running auto right now. Would you think it would be better to disable turbo and OC? I feel OCing with turbo would yield better overall results, but I could be wrong. The cooler I am using is the Noctua NH-U12P. My motherboard is the ASRock P55 Deluxe and I'm using 4GB DDR3 1333 Ripjaws. I'm looking to get the most stable OC while maintaining decent temps, but 65-66C seems kind of hot.

EDIT: My ram voltage is currently 1.6V, forgot to add that before.

 

[RussianSensation]

Ya I think those ripjaws will do even lower. Try setting 1.56V-1.57V in the BIOS. See if they are stable. Mine are stable at just 1.55V at DDR3-1600 CL7.

Now, if you want 65-66*C then you are not going to go much higher.

21x166 = 3.5ghz. At 166 base clock, QPI of 1.250V should be sufficient (maybe even stock). Try that and 1.300Vcore and see how that goes.

 

[yolt]

I tried your suggestion, but I can't even get it to boot at 1.3Vcore if I'm running at 3.5GHz. Since I have turbo enabled, when it runs only one core the actual GHz is around 4.2GHz or so, which requires a lot of voltage for some reason. My actual RAM isn't overclocked, as I kept it running at DDR3 1340 to test my CPU limits first.

I'm trying to find out what temps are safe for this type of CPU. When I run Prime95 I'm anywhere from 67-70C at 21x170. I'm pretty sure these temps are too high, although I can run a torture test with no problem. Another question I have is: Do you guys think it's better to have a lower overall OC, or to disable turbo and go with the highest clock speed possible? It seems like 3.56GHz is about the limit right now (with turbo enabled), and I'm using a vcore voltage of 1.40, which is most likely pushing the limits. Would you recommend I dial down my OC and reduce voltage, or are mid up upper 60C temps OK? Should I attempt to get my highest OC with turbo disabled? Any input would be greatly appreciated!

 

[MacAttack]

I am no expert and I have been trying to OC my i7 860 on an ASRock board for a week. I am only stable at 3.8GHz. Temps spike to mid-70s running IntelBurn but are steady at around 65-68 degrees.

I doubt I will see 4GHz stable on my combination. Since OC'ing was not critical, I am OK with it. If I had to do it over again, i7 920 D0/X58 is the better way to go for OC'ing.

 

[latch]

My i860 with the same fan and 8gb of 1600 ripjaw O/C'd to 3.5 without any additional voltage and Turbo Mode still on. Under load (IntelBurn test), my CPU sits at just over 41C. I'm on gigabyte board. At idle they sit at around 20C

 

[Ben90]

FYI im saving this to my HDD Idontcare, ill try to use it everyday

Quote from: Idontcare (forum hero)

Anything below TJmax is fine if you don't mind your CPU's expected lifetime to be "on the other side" of the 3yr warranty period. (meaning 3.1yrs or some such)

The QA engineering that goes into the process development itself is all geared towards ensuring this much just from a minimization of extenuating liabilities standpoint to Intel's books.

There is no single temperature threshold above which your cpu's lifetime suddenly diminishes. It is a continuous function that is dependent on an exponential of the operating temperature thanks to the physics that underlie the Arrhenius equation.

As a rule of thumb, for every 10C higher your operating temps the expected lifetime of your CPU is reduced by 50% (think of half-life). Whatever your expected cpu lifetime is if operating at 50C, call it X years, you can expect that lifetime to be cut in half if you operate your cpu at 60C, so X/2 years, and again cut in half once more if you operate it at 70C, so X/4 years, etc.

That may sound dire but understand the lifetime is engineered into the IC from the "top-down" in terms of the thermal specs. Meaning your thermal spec was set for your chip with the desire to minimize the number of in-field fails that would occur under warranty.

So making the assumption that your CPU has an expected lifespan equal to (really we should assume greater than as Intel would not be silly enough to make the mean of the distribution equal to their warranty period and then have to deal with the entire left-hand side of the distribution failing under warranty) the standard warranty period (3yrs) when operating at TJmax is a reasonable assumption. Then for every 10C below TJmax you operate the chip you should double the expected lifespan.

If TJmax is 90C and you operate at 80C then a very reasonable lower-estimate of your CPU's expected lifespan would be 6yrs (2 x 3yrs warranty period). If you operate at 70C then 2x2x3yrs = 12yrs expected lifespan.

What is the basis for my arguing this? At TI we required our process technology to be developed so as to enable the minimum lifetime requirement of 10yrs operating at max spec'ed operating voltage and max spec'ed operating temps in continuous 24/7 operation. It is SOP for the industry.

Now where you can really cook your goose (cpu) is over-volting and running hot. It doesn't take much to be operating your CPU in a voltage/temperature regime that in combination the two factors contribute to lowering the expected lifespan of your CPU to something <1yr.

Not too mention there is always a distribution to the lifespan and your particular chip could have some intrinsic weakness/flaw in it that puts its expected lifespan at a value below the mean of the distribution and by operating at elevated temps and volts it is destined to fail substantially sooner than the warranty period. (I killed my QX6700 in something like 18 months, never operated above TJmax or above Vccmax, but had lapped the IHS so no warranty replacement for me)

 

[alyarb]

haha that's exactly what his personality needs. put "forum hero" under his name and a star-shaped badge.

 

[Ben90]

This forum sucks; there are no star-shaped badges... Im currently making him a badge but i need a catchphrase...any suggestions?

 

[alyarb]

heh "IN THE NAME OF DECENCY"

 

[Ben90]

Fixed, check out the link in the quote

 

[alyarb]

heh, he can't reject it now. it would be very undiplomatic.

it's actually pretty funny. i wonder if he'll think we're mocking him.

 

[RussianSensation]

Disable Turbo mode and start over.

You should be able to hit much higher speeds now. Back off the Vcore from 1.40V. That's a bit too much.

Set PLL to 1.86, QPI to 1.25, CPU voltage to 1.35.

This should get you to 3.9ghz. If not raise QPI to 1.36. Go from there. You shouldn't need above 1.40V core unless you are over 4.0ghz.

Also temperatures under 80*C are OK. I like to be in the 70-75 range. But your 1.40V core is the reason for such high temps.

 

[RussianSensation]

Originally posted by: latch
My i860 with the same fan and 8gb of 1600 ripjaw O/C'd to 3.5 without any additional voltage and Turbo Mode still on. Under load (IntelBurn test), my CPU sits at just over 41C. I'm on gigabyte board. At idle they sit at around 20C

Try using Real Temp, or Core Temp or HWMonitor to get correct load temperatures.

 

[Ben90]

I dont know if they fixed it recently; or if its different with 1156; but HWMonitor last time i checked (about 2 months ago) was plain wrong with 1336 systems, it was estimating the tjmax at around 110 *C when every other estimate puts it around 100 *C

 

[alyarb]

yeah i use coretemp.

 

[Idontcare]

Originally posted by: Ben90
FYI im saving this to my HDD Idontcare, ill try to use it everyday

Quote from: Idontcare (forum hero)

*snip*

Originally posted by: alyarb
heh "IN THE NAME OF DECENCY"

You guys, flattery will get you everywhere in life thanks for the kind words and for taking the time to craft that star-graphic. If a post of mine helps just one person then I consider it well worth my time for having drafted the post in the first place.

In the name of decency...you know that's the kindest thing I think you could have stated because if you really do get that impression of me from my efforts here then I can't think of better proof that my time here has been well served and well placed after all.

Thanks again, I really do appreciate the kindness.

 

[alyarb]

heh, the model courtier. you remind me of "the 48 laws of power" by robert greene.

 

[latch]

Originally posted by: RussianSensation
Try using Real Temp, or Core Temp or HWMonitor to get correct load temperatures.

Darn...reran with CoreTemp (I was using something else before which obviously sucked)...it's now hovering 60C under load.