Questions on i7-8700k Power Draw

[MCMunroe]

I upgraded to a i7-8700k from a i7-7700k. I spent the weekend trying to get the system up and running and tuned. I have noticed amazingly low Package TDP reading. Core Temp and XTU agree so I don't immediately feel I have a faulty reading.

For Example, Average Package Readings set to 4.9GHz all Core around 1.355v reading. I am using the XTU recent average over the last 30 second period of the test.

Idle: 11W, 0.780v
Cinebench: 78W, 1.315v
CPU-z Stress: 53W, 1.315v
Geekbench 4: 17W, 0.998v
x265 Encoding x2: 73W, 1.340v
(That is two software x265 encodings at the same time that hammer the AVX2)
Time Spy: 23W, 1.203v


My System:
System
Intel i7-8700k (delided, liquid metal)
EVGA Z730 FTW
Corsair Vengence DDR-2400 (hold over)
EVGA GTX 1080ti SC2 Hybrid
HP EX920 1TB NVME
Corsair HX750
DeepCool Genome II with 360mm AIO

I choose the EVGA Z370 FTW based off of Toms Hardware Review, that showed this board running VRM temps at about half the competition and much lower current draws as well.

Screen of my current XTU

Screen of Core Temp video encoding on i7-8700k

Screen of Core Temp video encoding on i7-7700k
https://s3-eu-west-1.amazonaws.com/uploads-eu.hipchat.com/268659/1733564/1yTULTFi6ROUcub/Desktop%20i7-7700k%20Thermal%20Grizzly.png


Looks like I actually am running a bit higher voltage than my old set up. I have several questions.

I thought that the Coffee Lake Chips broke TDP ratings
Are my readings just junk?
What is going on?
Am I just lucky?

 

[breakingfelony]

Hi,

Not sure if this might help you at all? http://www.tomshardware.co.uk/answers/id-3779720/8700k-power-draw.html to me it sounds like your won with the CPU.

 

[MCMunroe]

Oh, my other question. There is a large difference between measured Voltage and set Voltage. When people are talking about there voltage for an overclock are they saying the set BIOS voltage or the read Voltage at load?


I will use my Killawatt to read the power draw from the wall as a sanity check. If the system draws less than the 7700k, the software readings may be correct. If the Killawatt reads 50 watts higher than the 7700k as the other reports of the 8700K OC running at 150W, than the readings are just bogus.

 

[MCMunroe]

LIES LIES AND MORE DECEPTION
I got out the Killawatt meter. And The reported Package TDP does not line up at all compared to the previous Kabylake and Skylake systems.

Is Intel lying or EVGA's motherboard?

 

[jankerson]

I upgraded to a i7-8700k from a i7-7700k. I spent the weekend trying to get the system up and running and tuned. I have noticed amazingly low Package TDP reading. Core Temp and XTU agree so I don't immediately feel I have a faulty reading.

For Example, Average Package Readings set to 4.9GHz all Core around 1.355v reading. I am using the XTU recent average over the last 30 second period of the test.

Idle: 11W, 0.780v
Cinebench: 78W, 1.315v
CPU-z Stress: 53W, 1.315v
Geekbench 4: 17W, 0.998v
x265 Encoding x2: 73W, 1.340v
(That is two software x265 encodings at the same time that hammer the AVX2)
Time Spy: 23W, 1.203v


My System:
System
Intel i7-8700k (delided, liquid metal)
EVGA Z730 FTW
Corsair Vengence DDR-2400 (hold over)
EVGA GTX 1080ti SC2 Hybrid
HP EX920 1TB NVME
Corsair HX750
DeepCool Genome II with 360mm AIO

I choose the EVGA Z370 FTW based off of Toms Hardware Review, that showed this board running VRM temps at about half the competition and much lower current draws as well.

Screen of my current XTU

Screen of Core Temp video encoding on i7-8700k

Screen of Core Temp video encoding on i7-7700k
https://s3-eu-west-1.amazonaws.com/uploads-eu.hipchat.com/268659/1733564/1yTULTFi6ROUcub/Desktop%20i7-7700k%20Thermal%20Grizzly.png


Looks like I actually am running a bit higher voltage than my old set up. I have several questions.

I thought that the Coffee Lake Chips broke TDP ratings
Are my readings just junk?
What is going on?
Am I just lucky?

Something off with the BIOS settings.

Must be a TDP limiter setting in the BIOS, need to check that and disable it or turn it off.

The 8700K should be pulling about 140W under stress testing.

 

[MCMunroe]

Something off with the BIOS settings.
Must be a TDP limiter setting in the BIOS, need to check that and disable it or turn it off.
The 8700K should be pulling about 140W under stress testing.

Yes, I read the Toms Hardware review of the EVGA Z370 FTW about the odd setting for the Core IIC Max limit, I increased the Core IIC Max to unlimited first thing.

The point is the wall plug is drawing was more power than the previous CPU, where as the 7700k power readings looked right the 8700k readings look to be off by about half.