Single core overclock i7-7700k

[parmi]

I am trying to overclock my i7-7700k.


System specs:

• CPU: i7-7700k @ 4.20 GHz (Turbo boost: 4.5GHz) [delidded]
  
• Mobo: Asus Maximus IX Extreme
  
• GPU: Gigabyte - GTX 1080 Ti Waterforce WB Xtreme Edition 11G
  
• RAM: 32GB - G.Skill - Trident Z RGB - DDR4 3600Mhz - 32GB (8GBx4) - 16-16-16-36
  
• PSU: Seasonic - PRIME 850 W Titanium
  
• Custom Cooling system:
  
• Radiator: x2 radiator (520x30x60mm)
  
  
• Radiator FAN: x8 Noctua (120x120x15mm)
  
  
• Pump: EK-XRES 140 Revo D5
  
  

At the moment these appear to be the two stable configurations:

4.9GHz Config

• CPU ratio: x49
  
• Vcore in BIOS: 1.375 V
  
• Vcore mode: manual
  
• XMP profile: enable (DDR4 - 3600MHz)
  
• CPU integrated GPU (iGPU): Enabled
  
• LLC: 5
  
• AVX offset: x0
  
• Windows 10 power management: High performance
  
• Vcore idle (HWiNFO64): 1.376 V
  
• Vcore Stress (HWiNFO64): 1.366 V
  
• Vcore idle (measured*): 1.384 V
  
• Vcore stress (measured*): 1.371 V
  
• OCCT stress temperature (AVX2): 74 °C
  

5.0GHz Config

• CPU ratio: x50
  
• Vcore in BIOS: 1.405 V
  
• Vcore mode: manual
  
• XMP profile: disabled
  
• Integrated GPU (iGPU): disabled
  
• LLC: 5
  
• AVX offset: x0
  
• Windows 10 power management: High performance
  
• Vcore idle (HWiNFO64): 1.408 V
  
• Vcore Stress (HWiNFO64): 1.398 V
  
• Vcore idle (measured*): 1.414 V
  
• Vcore stress (measured*): 1.402 V
  
• OCCT stress temperature (AVX2): 66 °C
  

*FLUKE 179 multimeter using the average function and measuring for 1 minute

With the 5GHz configuration if I enable the XMP profile or the iGPU I do not pass the OCCT test or the system crashes with a blue screen, at 5.1GHz the CPU is always unstable (regardless of XMP profile or iGPU).

Now I'm trying to set a different ratio for each core, in particular I'm trying this configuration:

• CPU core 0 ratio: x51
  
• CPU core 1 ratio: x50
  
• CPU core 2 ratio: x50
  
• CPU core 3 ratio: x50
  
• Vcore in BIOS: 1.405 V
  
• Vcore mode: manual
  
• XMP profile: disabled
  
• CPU integrated GPU (iGPU): disabled
  
• LLC: 5
  
• AVX offset: x0
  
• Windows 10 power management: High performance
  

With this configuration I passed a one hour OCCT (AVX2) test without any problems, but I noticed something odd with the clock reported by HWiNFO64.

When the system is in idle I have noticed that the core clocks keep jumping between 5.0GHz and 5.1GHz, sometimes all are at 5.1GHz, other times all are at 5.0GHz, and some time some are at 5.0GHz and others at 5.1GHz.




Then when I started a stress test (OCCT - AVX2) all cores were always at 5.0GHz, they didn't touch 5.1GHz even for a moment.

Can anyone explain to me what is happening?

I would have expected core 0 to be fixed at 5.1GHz and all others at 5.0GHz, why the clocks keep jumping between 5.0GHz and 5.1GHz?



Any suggestions are appreciated, thanks.

[Nate152]

Hi Parmi,

The clock speeds are fluctuating due to how much load is being applied to the cpu, I do see they hit 5.1GHz as the maximums are showing. To get the cores to run at a constant overclock, set the windows power plan to high performance.

When using one monitor with a dedicated gpu, I let the iGPU disabled.

It seems your memory is unstable, what can help is raising these voltages:

CPU System Agent voltage: 1.25v - 1.30v
CPU VCCIO voltage: 1.25v - 1.30v

I have a delidded 7700k that can run at 5.2GHz with 1.44v.

See how it goes after raising those voltages.

Instead of using a per core overclock, try "Sync all Cores".

[parmi]

Nate152 wrote:
Hi Parmi,

The clock speeds are fluctuating due to how much load is being applied to the cpu, I do see they hit 5.1GHz as the maximums are showing. To get the cores to run at a constant overclock, set the windows power plan to high performance.

When using one monitor with a dedicated gpu, I let the iGPU disabled.

It seems your memory is unstable, what can help is raising these voltages:

CPU System Agent voltage: 1.25v - 1.30v
CPU VCCIO voltage: 1.25v - 1.30v

I have a delidded 7700k that can run at 5.2GHz with 1.44v.

See how it goes after raising those voltages.

Instead of using a per core overclock, try "Sync all Cores".

Hi Nate152,

Thanks for the reply.
My power management is already set to high performance.

I use this PC for both streaming and gaming, I was wondering if Stream Labs benefits from having the iGPU active, do you know something about?

1.44V seems high to me, how long ago did you set your i7-7700k to 1.44V? do you use this overclock all the time (24/7)?
I have read several forums that a vcore greater than 1.4V will reduce the CPU life expectancy faster

I try to follow your suggestion with CPU System Agent and CPU VCCIO

[Nate152]

Well, cpu degredation is possible when overclocking and how fast it starts really depends on temperature and as you said how much voltage and quality of the cpu.

Intel recommends a maximum of no more than 1.52v for the 7700k so up to 1.45v I feel safe with, I ran it there 24/7 for five years until I recently upgraded.

Here is a video of my 7700k playing watchdogs 2 at 5.3GHz with 1.52v.

[parmi]

Nate152 wrote:
Well, cpu degredation is possible when overclocking and how fast it starts really depends on temperature and as you said how much voltage and quality of the cpu.

Intel recommends a maximum of no more than 1.52v for the 7700k so up to 1.45v I feel safe with, I ran it there 24/7 for five years until I recently upgraded.

Here is a video of my 7700k playing watchdogs 2 at 5.3GHz with 1.52v.

Wow, 1.52v!! You have been brave!

If your CPU has lasted at least 5 years with a vcore of 1.45v I think I'll also try my CPU up to 1.45v

One last question have you ever tried to measure your vcore with a multimeter? are you sure your vcore is really 1.45V?

[Nate152]

Yes voltages are correct, I also use HWinfo.

I used Thermal Grizzly Conductonaut between the die and IHS, Kryonaut between the IHS and water block, liquid cooled with the Koolance ERM-2K3U cooling unit.

I saw a -15c temp drop delidding my 7700k.

If you used similar and have good cooling, temps shouldn't be much of a problem with 1.45v.

I'm using the ROG Strix Z690-F Gaming Wifi with the 12700KF overclocked to 5.3GHz with 1.47v.

Here's a screenshot of HWinfo, click the pic to make it bigger.

[parmi]

Nate152 wrote:
Yes voltages are correct, I also use HWinfo.

I used Thermal Grizzly Conductonaut between the die and IHS, Kryonaut between the IHS and water block, liquid cooled with the Koolance ERM-2K3U cooling unit.

I saw a -15c temp drop delidding my 7700k.

If you used similar and have good cooling, temps shouldn't be much of a problem with 1.45v.

I'm using the ROG Strix Z690-F Gaming Wifi with the 12700KF overclocked to 5.3GHz with 1.47v.

Here's a screenshot of HWinfo, click the pic to make it bigger.

When I bought the CPU (5 years ago) I requested the delid service, I guess they used the same paste you used.
I wonder if after 5 years I should delid again and change the liquid metal between the die and IHS.
What do you suggest to me?