2500k @ 5GHz?

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Essence_of_War

Platinum Member
Feb 21, 2013
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Asking was trying to suggest some settings you guys recommend as I've already tried getting stable at 4.6GHz and had no luck.

With SB, if you're not stable, it's usually as straightforward as adding voltage and hoping your cooling method can deal with the extra heat. Keep incrementally bumping up the voltage, testing for stability, and checking if your temps are in a safe zone.

Personally, I'm not sure that the H60 is the weapon I'd take to the metaphorical 5 GHz gunfight, though.
 

2is

Diamond Member
Apr 8, 2012
4,281
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Considering an H60 is at best only as good as a mid range air cooling setup, I'd say not likely.
 

996GT2

Diamond Member
Jun 23, 2005
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You need a pretty "golden" chip to do 5 GHz stable. I'd say only about 5-10% of chips can run 5 GHz completely stable at less than 1.5V. Booting and running a couple of benchmarks at 5 GHz is a completely different story from being able to run 5 GHz stably all the time.

I got lucky and my 2700K will do 5 GHz stably at only 1.38V, but one of the 2500Ks I had before the 2700K needed a lot more voltage to hit 5 GHz. Even at 1.38V, I need a high end air cooler with push-pull 120mm fans to keep it cool at full load. A 2500K will run cooler at 5 GHz due to the lack of Hyper-Threading, but I still doubt a H60 is enough, especially since you will most likely need much more than 1.38V to make it fully stable at 5 GHz.

These are the temps I get on my 2700K @ 5 GHz, 1.38V, using a Thermalright HR-02 with 2x Gentle Typhoon AP-15s in push-pull.

sI5Pz.jpg


Also, the motherboard you have isn't very good in terms of voltage control options, and the VRM setup isn't a very good one either (looks like it only has 4 phases for CPU, 2 for iGPU). To do 5 GHz, you would ideally need to upgrade your motherboard as well.
 
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guskline

Diamond Member
Apr 17, 2006
5,338
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Getting a 2500k to run at 5 Ghz and getiing it to run stable are two VERY different things. What stress tests did you perform on your friend's machine?
 

Eric1987

Senior member
Mar 22, 2012
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I didn't perform any just normal day to day usage. What voltage do you guys recommend at 4.6-4.7GHz?
 

996GT2

Diamond Member
Jun 23, 2005
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I didn't perform any just normal day to day usage. What voltage do you guys recommend at 4.6-4.7GHz?

There is no "recommended" voltage. If you have a crap chip, you might need 1.5V to hit 4.6 GHz stable. If you have a golden chip, you might be able to do 4.6 GHz at 1.25V.

Also, normal day to day usage doesn't stress the CPU much. Without running a CPU-intensive task like Prime95 for 12+ hours, you cannot say that a CPU is stable at a certain clock speed.
 

toyota

Lifer
Apr 15, 2001
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Prime 95 for 12 hours is silly and not even recommend with Haswell. just run some stress tests like Intel Extreme Tuning and the ASUS RealBench 2.1. after a few passes on each of those fire up a few different games and play them at max settings but low res and no AA. Crysis 3 will find an unstable oc for me much better than any cpu test like Prime 95 or even the ones I mentioned.
 

sze5003

Lifer
Aug 18, 2012
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I have had my 2500k for a bit over 2 years now I think. I just overclocked it a few weeks ago and it would only go to 4.2ghz with +.04 additional turbo and an offset of +.005. My mobo doesn't seem to have a way to turn off the turbo option so I can't set it manually. But I don't even need to overclock, can max out almost any game at 1080p.

I ran prime 95 for 25+ minutes and then did 10 passes with Intel burn test.
 

Eric1987

Senior member
Mar 22, 2012
748
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2is

Diamond Member
Apr 8, 2012
4,281
131
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I doubt anyone is going to delete a thread because you're upset that people are telling you the truth about your "stability" and realistic expectations in achieving 5GHz given your current setup.

But yes, the types of questions you should ask here are the ones you want honest answers to and not ones you'll get mad when you don't get the answer you wanted to hear.
 

Eric1987

Senior member
Mar 22, 2012
748
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I'm not upset. It just ended up being a pointless thread. Telling me the truth about my stability? I am not trying to win an OC contest so what I deem stable is just that. Stable. And no one offered anything that actually answered my question. If someone asked what it would take to get 4.5GHz stable you know what I would say? Adjust the multiplier and watch your temps to see that they don't go too high. And give a recommended threshold. That would be answering the question. I've never achieved stable 4.7Ghz so if anyone has achieved it I would of liked their setup and temps when they stressed it. But no one could do something that simple.
 

toyota

Lifer
Apr 15, 2001
12,957
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because it does not really matter what their setup is. I could use 5 different 4770k cpus without changing anything else and have vastly different results for each cpu.
 

Eric1987

Senior member
Mar 22, 2012
748
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I have been overclocking for damn near 15 years I know damn well what people are saying. My question STILL doesn't change. I started my OC'ing on a Pentium 4 1.8GHz so don't tell me I don't grasp it.
 

toyota

Lifer
Apr 15, 2001
12,957
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I have been overclocking for damn near 15 years I know damn well what people are saying. My question STILL doesn't change. I started my OC'ing on a Pentium 4 1.8GHz so don't tell me I don't grasp it.
I don't care how long you have been overclocking, you still do not grasp what people are telling you here in this thread.
 

Eric1987

Senior member
Mar 22, 2012
748
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Yes I do. Again I shall reiterate myself. Just like if my friend had the same chip or similar I would ask him his experiences and take it into account when I OC my chip.
 

996GT2

Diamond Member
Jun 23, 2005
5,212
0
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Yes I do. Again I shall reiterate myself. Just like if my friend had the same chip or similar I would ask him his experiences and take it into account when I OC my chip.

If you've been overclocking for 15 years and actually knew what you were doing, you'd know that it's not very hard to see if a Sandy Bridge chip will do 5 GHz. They're about as easy as it gets when it comes to overclocking.

1) Set voltage to 1.5V, highest LLC, all power saving features off. If your motherboard doesn't let you adjust LLC, get a better motherboard.
2) Set multipler to 50 and BCLK to 100
3) If your CPU doesn't boot, then it's most likely not a good enough chip to do 5 GHz stable.
 

BonzaiDuck

Lifer
Jun 30, 2004
15,732
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The OP's friends are claiming 5.0 Ghz -- likely as a matter of bragging rights. I am skeptical about this. First -- air-cooling wouldn't likely be sufficient to handle the temperatures for such an overclock -- whether 2500K, 2600K -- even 2700K.

People often get their systems "tentatively stable" -- meaning it boots into Windows and allows for use of some desktop apps. then they run some stress-tests, perhaps 10 iterations of IBT "Standard" or "High" and call it a day. But that doesn't cut the mustard for "rock-stable 24/7."

It's my understanding that the last known published spec for an Intel "safe" voltage upper-boundary was 1.38V for Nehalem. [Correct me if this is inaccurate.] The Nehalems generally went into production using a 32nm lithography. Sandy Bridge also employs a 32nm lithography, therefore by a simple inference, it should have a similar safe upper limit of 1.38V.

I have a "pretty good" i7-2600K with superb air-cooling. I don't fiddle around with insufficient voltage settings, and I stress-test with LinX or IBT for 50 iterations. After it passes those stress-tests, I may add about 4 to 5mV in the voltage settings.

At 4.7 Ghz, my monitoring software under severe load shows a minimum actual voltage of between 1.355 and 1.36V. The unloaded "turbo" voltage at the end of a stress-test will typically register at about 1.37 to 1.38V.

I might TRY for 4.8, now that I have my temperatures pegging a maximum of 69.5C (4-core average maximum). But I'll have to up the voltage, and the recorded voltages are likely to be 1.37/1.38 severe load, and maybe 1.4V for the unloaded turbo reading at stress-test end.
 

ethebubbeth

Golden Member
May 2, 2003
1,740
5
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I can't seem to get more than 4.3ghz out of my 2500k regardless of voltage. I've settled at 4.3ghz @ 1.276 V. Definitely YMMV.
 

Headfoot

Diamond Member
Feb 28, 2008
4,444
641
126
I'm not upset. It just ended up being a pointless thread. Telling me the truth about my stability? I am not trying to win an OC contest so what I deem stable is just that. Stable. And no one offered anything that actually answered my question. If someone asked what it would take to get 4.5GHz stable you know what I would say? Adjust the multiplier and watch your temps to see that they don't go too high. And give a recommended threshold. That would be answering the question. I've never achieved stable 4.7Ghz so if anyone has achieved it I would of liked their setup and temps when they stressed it. But no one could do something that simple.

Google a Sandy Bridge overclocking guide.

I got 4.7 on my 2500k by turning on the PLL overvoltage, setting multi to 47 and giving it 1.4125v. I could run this stable with an H80 at max fan speed and my temperatures were still getting higher than I liked ~75 in normal usage. So I now run it at 4.6 @ 1.38 because the 100 mhz wasn' worth all that extra voltage imo and I don't break 70 in normal usage anymore. H60 is probably insufficient for voltage over 1.4 generally