CPU Intel 'T' processors, actual power usage

[robbee]

I'm planning on making a low-power build, and for that I'm looking at the intel 'T' processors (i3 6100t, i3 6300t, etc.). Their TDP is listed at 35w, which is quite a lot lower than their regular versions. However, I cannot find any reviews or data on their actual power usage, and if the slightly lower clocks actually account for a much lower power draw. Has anyone ever read about this or tested it themselves?

 

[robbee]

I've managed to answer my own question, found this great review: http://www.xbitlabs.com/articles/cpu/display/core-i5-4670s-4670t.html

Turns out the 'S' and 'T' versions have no other differences than a lower clockrate. No better binning or anything like that. You could get the same result by just downclocking a regular version. Not too impressive...

 

[GuilleAcoustic]

Answer is here for an 84W i7 versus a 35W i7 (Haswell refresh): https://smallformfactor.net/forum/threads/cpu-selection-question.758/#post-14586

Edit: The 4670T from your review is a 45W CPU, not a 35W one.

 

[robbee]

Answer is here for an 84W i7 versus a 35W i7 (Haswell refresh): https://smallformfactor.net/forum/threads/cpu-selection-question.758/#post-14586

Edit: The 4670T from your review is a 45W CPU, not a 35W one.

Thanks for the link. I'm afraid there's one thing missing from that table though: how does the 4790K perform and how much power does it use at the clocks of the 4690T? Turns out they're pretty much identical, so I may as well just take the regular version and downclock it myself

 

[QinX]

I'll see if I can run that test for you, my 4785T runs at 2.8GHz when doing a Cinebench R15 run so I'll try to get the same clock on the 4790K and see what the lowest stable voltage is.

I'd like to try undervolting the 4785T but the board it is in doesn't have any BIOS options for that.

 

[robbee]

I'll see if I can run that test for you, my 4785T runs at 2.8GHz when doing a Cinebench R15 run so I'll try to get the same clock on the 4790K and see what the lowest stable voltage is.

I'd like to try undervolting the 4785T but the board it is in doesn't have any BIOS options for that.

That would be great. Thanks!

 

[Hahutzy]

Also with their Skylake line, "S" processors no longer exist; 65W is now standard

 

[Josh | NFC]

Just built three systems with 1070s. Two were identical with 6700Ts and one had a 6700K.

Measured with a WattsUp? PRO in 3Dmark Timespy
6700T system 190w
6700K system 225w

BBBBBoooNUS round: 6700K with 1080 270w

Pretty much the same in Uni-engine Valley.

Not science or anything, just observations. Need to do more testing.

 

[Kmpkt]

Any chance you'd be able to under lock the 6700K to similar clocks to the 6700T and redo the profile? Would be really curious to see if a stable underclock can be easily done and if so what the wattage difference would be if any.

 

[Josh | NFC]

Any chance you'd be able to under lock the 6700K to similar clocks to the 6700T and redo the profile? Would be really curious to see if a stable underclock can be easily done and if so what the wattage difference would be if any.

Marcparis has some info in his thead on the undervolting but I don't think regarding wattage.