tweaking and power limits of a CPU

[Islam Ghunym]

I got an 8 cores 16 threads coffee lake CPU in hand base 2.1 GHz boost 39-4.4 GHz. Obviously looks to be a mobile sample. The power budget is 45W. The main purpose is to get most out of this sample without exceeding the power limit (since it is a mobile CPU).

I increased the vcore to 1.4v and pushed boosting to 4.6-5.1. that resulted in less multi core performance and more single threaded performance (Cr15 multi 1300>>1207, single 192>>216) now I am sure the CPU is going to perform better in single threaded applications aka: gaming, adobe photoshop... etc. The next step is tweaking the uncore ratio and here I got lost a bit and need help. If I increase the uncore ratio that would increase the power usage and because I am limited to 45W... I may get less performance in some cases? in single threaded applications OR...... the CPU would switch the core and uncore ratio automatically when power limited to achieve the maximum performance at the given power limit? I wanna know about coffee lake behaviour so I can guess better.

 

Running benchmarks on different applications is gonna be very time consuming in my case as I am not prepared for that so a simple answer would save my time and be appreciated

[RONOTHAN##]

Uncore is the frequency at which the CPU can access the cache and other cores, it in itself shouldn't really affect power draw much, if at all. You can do a bit of testing, but unless you're raising voltages like the System Agent (what the Uncore runs on) the only power consumption increases will be from the CPU running more efficiently per clock which should be well under a watt at most. 

[Islam Ghunym]

6 hours ago, RONOTHAN## said:

Uncore is the frequency at which the CPU can access the cache and other cores, it in itself shouldn't really affect power draw much, if at all. You can do a bit of testing, but unless you're raising voltages like the System Agent (what the Uncore runs on) the only power consumption increases will be from the CPU running more efficiently per clock which should be well under a watt at most. 

Ah, so the uncore ratio by itself doesn't increase power, but the extra power draw is there because of cores being loaded more and performing better when the uncore ratio increased. Is that what you mean? If it is like that then I should increase it to maximum and not be worried about it, right?

[unclewebb]

6 hours ago, Islam Ghunym said:

without exceeding the power limit (since it is a mobile CPU)

You can increase the power limits even if it is a mobile CPU. 

 

6 hours ago, Islam Ghunym said:

I increased the vcore to 1.4v

Increasing the voltage will increase power consumption which will make the CPU throttle more to stay under the 45W power limit. Most people with mobile CPUs do the opposite. Lower voltage to lower power consumption so the CPU can run faster. 

 

Are you using a laptop computer or did you install this mobile CPU into a desktop board? Post a CPU-Z screenshot. If there are no settings in the BIOS to control the power limits then use Intel XTU or use ThrottleStop.

[Islam Ghunym]

23 minutes ago, unclewebb said:

You can increase the power limits even if it is a mobile CPU. 

 

Increasing the voltage will increase power consumption which will make the CPU throttle more to stay under the 45W power limit. Most people with mobile CPUs do the opposite. Lower voltage to lower power consumption so the CPU can run faster. 

 

Are you using a laptop computer or did you install this mobile CPU into a desktop board? Post a CPU-Z screenshot. If there are no settings in the BIOS to control the power limits then use Intel XTU or use ThrottleStop.

Lets be specific and avoid unnecessary conversation out of the topic. I asked a simple question. none of the written is the answer . If you don't have an idea about the answer please don't consider writing anything else. Thanks for taking time writing your reply by the way.

[RONOTHAN##]

1 hour ago, Islam Ghunym said:

Ah, so the uncore ratio by itself doesn't increase power, but the extra power draw is there because of cores being loaded more and performing better when the uncore ratio increased. Is that what you mean? If it is like that then I should increase it to maximum and not be worried about it, right?

You'd have to worry about stability of its an unlocked chip, but running it at the max stable frequency should be fine