Manual vs Adaptive Overclock

[Steve N. Mavronis]

I have my ASUS Z170i motherboard 6700K overclocked to 4.6Ghz @ 1.35V and then set it to the recommended adaptive mode.

 

That's fine and no problems but what is the actual benefit to using adaptive mode vs manual mode other than power saving and full OC as needed?

 

I know on its face this may probably seem like a dumb question.

 

Also as far as the 1.35V that was an OC guide's recommended starting point for air cooling really the only value I've tried. Should I experiment with lower voltages or is that voltage generally fine to keep it there?

[don_svetlio]

1.35V is a bit high for Skylake

[Steve N. Mavronis]

6 minutes ago, don_svetlio said:

1.35V is a bit high for Skylake

Like I said that was an ASUS document recommended starting point for air cooling. What voltage range is considered stable and normal for 6700K at 4.6Ghz?

[don_svetlio]

2 minutes ago, Steve N. Mavronis said:

Like I said that was an ASUS document recommended starting point for air cooling. What voltage range is considered stable and normal for 6700K at 4.6Ghz?

I'd personally go for 1.3-1.32V - 1.35 is the max people would do with Haswell and for Skylake most run 1.3

[LeapFrogMasterRace]

You shouldn't just use the voltage someone tells you to, you have to do a stability test with different voltages until you find what is stable for your cpu.  At 1.35 you could risk shortening the lifespan of the processor, adaptive mode helps keep the cpu voltage down when it does not need to be high such as browsing the web or watching videos this can help extend the lifespan a bit. 

[Steve N. Mavronis]

Thanks retesting in manual mode at 1.3V and will see if I can go lower. 

 

[Edit[ Running the ASUS RealBench test and it crashed with a Clock_Watchdog_Timeout. Will try it at 1.32v next. 

 

Well that failed too. Trying 1.33v

[Steve N. Mavronis]

ASUS RealBench survived 4.6Ghz @ 1.33V

 

I monitored temps with CPUID HWMonitor. The highest 2 of the 6700K cores got was 80c. Any higher it probably would have crashed again.

 

Mind you it was only 1 pass. But as an indication should I increase to 1.34V or possibly downclock to 4.5Ghz?

[Tech Deals]

30 minutes ago, Steve N. Mavronis said:

ASUS RealBench survived 4.6Ghz @ 1.33V

 

I monitored temps with CPUID HWMonitor. The highest 2 of the 6700K cores got was 80c. Any higher it probably would have crashed again.

 

Mind you it was only 1 pass. But as an indication should I increase to 1.34V or possibly downclock to 4.5Ghz?

The question I ask myself is...  Is 100 MHz against 4.5 GHz worth the risk of system stability?

 

Are you on air cooling?  4.5Ghz and 1.32v might be a fair setting for that.

[Steve N. Mavronis]

51 minutes ago, Tech Deals said:

The question I ask myself is...  Is 100 MHz against 4.5 GHz worth the risk of system stability?

 

Are you on air cooling?  4.5Ghz and 1.32v might be a fair setting for that.

I'm wondering that too. Yes I'm on air cooling with the Thermalright Silver Arrow ITX. When I was at 4.6Ghz and 1.35V everything was very stable. The debate is if 1.35V is normal for that or too high, along with adaptive voltage mode being used. I suppose 4.6Ghz for me is pushing the limits of cooling and stability?

[EDIT] Ok I'm at 4.5Ghz now and 1.32V passed Asus RealBench and hottest core temps were 78c so 2c cooler than at 4.6Ghz.

Edited April 3, 2016 by Steve N. Mavronis

[Tech Deals]

1 hour ago, Steve N. Mavronis said:

I'm wondering that too. Yes I'm on air cooling with the Thermalright Silver Arrow ITX. When I was at 4.6Ghz and 1.35V everything was very stable. The debate is if 1.35V is normal for that or too high, along with adaptive voltage mode being used. I suppose 4.6Ghz for me is pushing the limits of cooling and stability?

[EDIT] Ok I'm at 4.5Ghz now and 1.32V passed Asus RealBench and hottest core temps were 78c so 2c cooler than at 4.6Ghz.

I honestly don't have any inside info as to the long term ability of Skylake to run at 1.35v.  One question to ask yourself (and anyone else reading this) is how long do you want your CPU to last?

 

You can probably run it at 1.5v, for awhile.  But "awhile" might be a month, or 3 months, or 6 months.

 

I have a i7-4770k overclocked to 4.4GHz on water cooling at 1.2v.  It will run at 4.6GHz if I give it 1.3v, but frankly the extra 200 MHz isn't worth the voltage to me.

[Steve N. Mavronis]

Yeah a lot of this just ends up being bragging rights to see what you can achieve. But in the end we want our computers to last a long time. I think a 12% CPU speed boost from 4.0Ghz to 4.5Ghz is still good. Frankly before I built this PC while researching my parts (https://pcpartpicker.com/b/96JV3C) wasn't really expecting to even hit 4.5Ghz, especially with my memory being at the rated 3200Mhz using XMP. 

 

Today I have my 6700K at 4.4Ghz at 1.28V and Asus RealBench passed so far but I didn't try lower than 1.275V yet. I'm debating on attempting 1.26V. CPUID HWMonitor reported the highest core temp was 71c at full stress test and the package TDP stayed less than 95W in the 80's.

Edited April 3, 2016 by Steve N. Mavronis

[Steve N. Mavronis]

I re-tested my 6700K overclock settings for a target of 4.5Ghz at minimum stable voltage with low CPU thermals and best benchmark performance. I measured temperature changes with CPUID HWMonitor. Based on my results below it looks like 2.80V is the most promising VCore setting for me to work with. 

Both RealBench and CineBench results seem to trend with one another. My test range was between 1.30V-1.27V in 0.01 increments between tests. I didn't even bother trying 1.26V because the results started trending lower at 1.27V and didn't expect any different other than more of a chance for instability. Here are my test runs and results:

Tue Apr 5 2016 18:26:58
4.5Ghz @ 1.30V 92.81W 74c Max Load
Image Editing: 197010 Time: 25.826
Encoding: 178348 Time: 53.76
OpenCL: 100032K Samples/sec: 2628
Heavy Multitasking: 180719 Time: 54.117
System Score: 144020
----------------------------
[CineBench CPU 968cb]

Tue Apr 5 2016 19:51:31
4.5Ghz @ 1.29V 92.62W 73c Max Load
Image Editing: 197807 Time: 25.722
Encoding: 178883 Time: 53.599
OpenCL: 100032K Samples/sec: 2628
Heavy Multitasking: 184375 Time: 53.044
System Score: 145267
----------------------------
[CineBench CPU 985cb]

Tue Apr 5 2016 20:19:42
4.5Ghz @ 1.28V 90.93W 73c Max Load
Image Editing: 197094 Time: 25.815
Encoding: 182499 Time: 52.537
OpenCL: 100032K Samples/sec: 2622
Heavy Multitasking: 183438 Time: 53.315
System Score: 145759
----------------------------
[CineBench CPU 989cb]

Tue Apr 5 2016 20:50:44
4.5Ghz @ 1.27V 89.68W 71c Max Load
Image Editing: 196850 Time: 25.847
Encoding: 181529 Time: 52.818
OpenCL: 100032K Samples/sec: 2626
Heavy Multitasking: 184090 Time: 53.126
System Score: 145618
----------------------------
[CineBench CPU 986cb]