Undervolting my CPU

[KylorLee]

im wondering im told you can undervolt your CPU by allowing it to use less power without hindering its overal performance can someone teach me how to do that?

[For Science!]

14 minutes ago, JohnDoe94 said:

 

1. Install a stress program, my recommendation would be RealBench. Other options: OCCT, Prime95, AIDA64 (In order of my personal preference)

  1.5 Install a hardware monitoring software like HWinfo64 too

2. Restart computer, go into the BIOS

3. Change voltage mode of CPU from auto to offset (may differ depending on motherboard)

4. Set a negative offset, perhaps try something like -0.1 volts, or -0.075 volts

5. Restart computer, go into the OS, and run the stress test for an extended period. Personal recommendation, 8 hours

  5.5 Keep an eye on temps, CPU frequency, and Vcore using HWInfo64 to make sure nothing funny is happening.

6. If computer doesn't bluescreen/freeze/crash, then this particular undervolt is deemed stable

7. Go back to number 4 and try some more undervolting (e.g. if -0.1 V was succesful, try -0.125 volts)

8. If at some point you hit the undervolt that starts crashing your computer when stress testing, go to the last successful undervolt

9. If at any point your system is so unstable it fails to POST, clear CMOS by either pulling the CMOS battery or if your motherboard has a dedicated jumper or switch, press that

[KylorLee]

Just now, For Science! said:

1. Install a stress program, my recommendation would be RealBench. Other options: OCCT, Prime95, AIDA64 (In order of my personal preference)

  1.5 Install a hardware monitoring software like HWinfo64 too

2. Restart computer, go into the BIOS

3. Change voltage mode of CPU from auto to offset (may differ depending on motherboard)

4. Set a negative offset, perhaps try something like -0.1 volts, or -0.075 volts

5. Restart computer, go into the OS, and run the stress test for an extended period. Personal recommendation, 8 hours

  5.5 Keep an eye on temps, CPU frequency, and Vcore using HWInfo64 to make sure nothing funny is happening.

6. If computer doesn't bluescreen/freeze/crash, then this particular undervolt is deemed stable

7. Go back to number 4 and try some more undervolting (e.g. if -0.1 V was succesful, try -0.125 volts)

8. If at some point you hit the undervolt that starts crashing your computer when stress testing, go to the last successful undervolt

9. If at any point your system is so unstable it fails to POST, clear CMOS by either pulling the CMOS battery or if your motherboard has a dedicated jumper or switch, press that

im using an ASROCK motherboard so if i choose to undervolt and underclock my CPU by lets say 1ghz how much longer would it last than what its currently set to would it be worth it it would produce less heat and less heat means longer life right?

[For Science!]

Just now, JohnDoe94 said:

im using an ASROCK motherboard so if i choose to undervolt and underclock my CPU by lets say 1ghz how much longer would it last than what its currently set to would it be worth it it would produce less heat and less heat means longer life right?

Let me look through my crystal ball..........nope I don't see anything.

 

Your CPU is going to have a life span that's far longer than its relevant life span. Sure less heat is longer life, but it's not like you will notice a performance degradation over the time where the 8700K remains relevant as a CPU.

[Mira Yurizaki]

22 minutes ago, JohnDoe94 said:

im wondering im told you can undervolt your CPU by allowing it to use less power without hindering its overal performance can someone teach me how to do that?

To add to what @For Science! said, there's two methods of undervolting: offset and overriding. What was described was using offset undervolting.

 

You can do overriding undervolting, but depending on the CPU, you may not get very far at stock clock settings before hitting stability issues. However, some processors may require so much voltage to achieve their maximum boost clock that you can dial down the boost clock a bit or set a fixed value and drop the voltage much lower. Unless you have absolutely top tier cooling, this may not result in a performance drop from sustained performance. For example, I set my Ryzen 2700X to a fixed 4.0 GHz but overridden the voltage to around 1.225. When running Prime95, The processor can remain at this speed for much longer than default settings, to where it drops to base clock speeds.

 

3 minutes ago, JohnDoe94 said:

im using an ASROCK motherboard so if i choose to undervolt and underclock my CPU by lets say 1ghz how much longer would it last than what its currently set to would it be worth it it would produce less heat and less heat means longer life right?

Yes, but the problem is we don't know how long processors are supposed to last to begin with. The processor could be fine for 20 years on stock.

 

The only practical reason to do this is just to generate less heat and consume less power.

[KylorLee]

 

Just now, Mira Yurizaki said:

To add to what @For Science! said, there's two methods of undervolting: offset and overriding. What was described was using offset undervolting.

 

You can do overriding undervolting, but depending on the CPU, you may not get very far before hitting stability issues. However, some processors may require so much voltage to achieve their maximum boost clock that you can dial down the boost clock a bit or set a fixed value and drop the voltage much lower. Unless you have absolutely top tier cooling, this may not result in a performance drop from sustained performance. For example, I set my Ryzen 2700X to a fixed 4.0 GHz but overridden the voltage to around 1.225. When running Prime95, The processor can remain at this speed for much longer than default settings, to where it drops to base clock speeds.

 

Yes, but the problem is we don't know how long processors are supposed to last to begin with. The processor could be fine for 20 years on stock.

 

The only practical reason to do this is just to generate less heat and consume less power.

would it be a good idea to undervolt my CPU or should i just leave it as it is cause undervolting does sound like a good idea for lowering my thermals meaning my CPU fan can run slower how would it effect games tho like if im wanting to reach 144fps in a game like overwatch

[KylorLee]

2 minutes ago, Mira Yurizaki said:

To add to what @For Science! said, there's two methods of undervolting: offset and overriding. What was described was using offset undervolting.

 

You can do overriding undervolting, but depending on the CPU, you may not get very far before hitting stability issues. However, some processors may require so much voltage to achieve their maximum boost clock that you can dial down the boost clock a bit or set a fixed value and drop the voltage much lower. Unless you have absolutely top tier cooling, this may not result in a performance drop from sustained performance. For example, I set my Ryzen 2700X to a fixed 4.0 GHz but overridden the voltage to around 1.225. When running Prime95, The processor can remain at this speed for much longer than default settings, to where it drops to base clock speeds.

 

Yes, but the problem is we don't know how long processors are supposed to last to begin with. The processor could be fine for 20 years on stock.

 

The only practical reason to do this is just to generate less heat and consume less power.

another question can a motherboard overclock a CPU without me having to do anything cause an 8700ks base clockspeed is 3.7 but when i look at my cpu its like 4.4ghz is that normal?

[For Science!]

Just now, JohnDoe94 said:

 

would it be a good idea to undervolt my CPU or should i just leave it as it is cause undervolting does sound like a good idea for lowering my thermals meaning my CPU fan can run slower how would it effect games tho like if im wanting to reach 144fps in a game like overwatch

Undervolting in itself doesn't impact fps (unless its unstable). However if you underclock by 1 GHz then you will see massive hits in a CPU intensive game like Overwatch. I assume this is 1080p or lower as well.

[KylorLee]

Just now, For Science! said:

Undervolting in itself doesn't impact fps (unless its unstable). However if you underclock by 1 GHz then you will see massive hits in a CPU intensive game like Overwatch. I assume this is 1080p or lower as well.

what if my motherboard automatically overclocks my CPU to its maximum performance what if i manual set the clock speeds back to base clockspeeds would my CPU still run games fine?

[For Science!]

Just now, JohnDoe94 said:

what if my motherboard automatically overclocks my CPU to its maximum performance what if i manual set the clock speeds back to base clockspeeds would my CPU still run games fine?

Your motherboard is not overclocking your cpu to its maximum performance, you are just confused about base and boost clock. This is even before we talk about MCE. Setting your CPU to base clock will incur a large penalty for performance.

[KylorLee]

Just now, For Science! said:

Your motherboard is not overclocking your cpu to its maximum performance, you are just confused about base and boost clock. This is even before we talk about MCE. Setting your CPU to base clock will incur a large penalty for performance.

so how much can i undervolt my 8700k before it becomes unstable where can i undervolt it to where its still stable and can run games fine with lower thermals?

[For Science!]

Just now, JohnDoe94 said:

so how much can i undervolt my 8700k before it becomes unstable where can i undervolt it to where its still stable and can run games fine with lower thermals?

Let me look through my crystal ball once again...........nope still nothing

 

This depends on so many parameters, but mainly how good the silicon is in your particular 8700K. No way to know unless you establish it yourself. I've already outlined the procedure.

[KylorLee]

Just now, For Science! said:

Let me look through my crystal ball once again...........nope still nothing

 

This depends on so many parameters, but mainly how good the silicon is in your particular 8700K. No way to know unless you establish it yourself. I've already outlined the procedure.

 

silicon?

[KylorLee]

1 minute ago, For Science! said:

Let me look through my crystal ball once again...........nope still nothing

 

This depends on so many parameters, but mainly how good the silicon is in your particular 8700K. No way to know unless you establish it yourself. I've already outlined the procedure.

look if i cant get a direct answer on how much i should undervolt my CPU im just gonna forget about it

[For Science!]

1 minute ago, JohnDoe94 said:

 

silicon?

you know....the rock that humans managed to convince to think? /s

 

Basically the quality of the 8700K.

[For Science!]

Just now, JohnDoe94 said:

look if i cant get a direct answer on how much i should undervolt my CPU im just gonna forget about it

Perhaps that is for the best for you. /thread

[xg32]

48 minutes ago, JohnDoe94 said:

im wondering im told you can undervolt your CPU by allowing it to use less power without hindering its overal performance can someone teach me how to do that?

if you are using intel parts or zen 1/zen+ do what @For Science! said, if you are using zen 2 parts, just use a negative voltage offset of either -0.05v (won't impact performance or -0.1v (might impact performance, use benchmarks before and after)

 

I use my 9900k at 1.05v 4.4ghz 95w most the time unless i'm playing some competitive game, power draw goes down by half compared to 5ghz, can't see the difference with chrome 

[For Science!]

Just now, xg32 said:

if you are using intel parts or zen 1/zen+ do what @For Science! said, if you are using zen 2 parts, just use a negative voltage offset of either -0.05v (won't impact performance or -0.1v (might impact performance, use benchmarks before and after)

He's on an 8700K. Tag, you're it!.