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i7-8700K VCCIO & VCCSA Voltage

TSyro
Beginner
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Hello,

I would like to ask about recommeneded max voltages for VCCIO and VCCSA on Coffee Lake CPU´s (i7-8700K) which should be used for standard 24/7 usage. I would like to know how high I can set these without being worried about possible quick degradation of IMC inside CPU.

Im running high speed RAMs in dual-channel on 4200MHz, CL16 (16-18-38-2) with lowered secondary timings.

I know that default voltages are 0,95V for VCCIO and 1,05V for VCCSA. And I also noticed that my motherboard allows me to set as max. for both of them 1,35V. When I try to set anything higher it already says: error invalid input - auto adjusted. And it sets it back to allowed max. - 1,35V.

My motherboard is ASROCK Fatal1ty Z370 Gaming K6.

Im currently using VCCIO 1,29V and VCCSA 1,32V.

Isnt this already too high?

Thanks a lot.

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idata
Employee
5,946 Views

Hello tomsyr11

 

 

Thank you for joining the community.

 

 

Looking into your case I see that you are searching for the max voltages of VCCIO and VCCS, allow me to share with that the voltages that are set on the default BIOS settings provided by the motherboard manufacturer are voltages that are safe for the PC usage, given that you are looking for different configuration could you let know what is the purpose of using the max voltages on the system? are you developing or programming with your system?

 

 

Regards,

 

Leonardo C.

 

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TSyro
Beginner
5,946 Views

Hello Leonardo,

thanks for answer.

Yes automatic sets VCCIO on 0,95V and VCCSA on 1,05V when RAMs runs on default DRR4 speed = 2133MHz but if I set it faster than what is default for this CPU (= 2666MHz) these voltages already needs to be increased to keep stablity. Im overclocking my system to get the maximum possible performace (thats the reason why Im asking about this). But I dont want to do this as cost of shortening lifespan of CPU by a lot. CPU speed is rising with faster RAM speed - mainly in games where Im limited from CPU/RAM side. So with the GTX 1080Ti when Im playing older games in lower resolutions and/or using lower graphics settings performance is often CPU/RAM side limited.

With current speed of 4200MHz in dual-channel, CL16 (16-18-38-2) with lowered secondary timings my motherboard by auto settings sets me on these voltages 1,25V on VCCIO and 1,35V on VCCSA. But automatic doesnt work well here - with these voltages my system isnt fully stable (IO too low and SA too high). The best configuration with speed of RAMs Im currently using seems to be 1,29V VCCIO and 1,32V VCCSA. I also know when these voltages are too low but also too high it causes instability. But I would like to know if these voltages aren´t already too high (especially about the VCCIO) for standard usage. If it would decrease CPU lifespan lets say for example from 25 years to 15-10 years that doesnt matter to me. But if CPU would get affected already like in 5 years by running these voltages then I would rather lower them and deal with a bit slower RAM speed.

If it is possible to provide some further details about these voltages I would be glad, thanks a lot.

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idata
Employee
5,946 Views

Hello

 

Thank you for your response.

 

 

I understand the propose of your inquiry, looking into information about the case allow me to share with you the information available from Intel about overlooking, you can refer to the following link:

 

 

https://www.intel.com/content/www/us/en/gaming/overclocking-intel-processors.html https://www.intel.com/content/www/us/en/gaming/overclocking-intel-processors.html

 

 

Please bear in mind that altering clock frequency or voltage may damage or reduce the useful life of the processor and other system components, and may reduce system stability and performance. Product warranties may not apply if the processor is operated beyond its specifications. Check with the manufacturers of system and components for additional details.

 

 

Regards,

 

Leonardo C.

 

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idata
Employee
5,946 Views

Hello tomsyr11

 

 

I was checking your case and would like to know if you need further help. If so, please do not hesitate in replying back.

 

 

Regards,

 

Leonardo C.

 

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