i7 T vs S vs K

[ryrynz]

Can someone tell me if Intel's T series processors are different in any other way besides the multiplier and the turbo? Essentially could I purchase a 4770K, change the multiplier to match as closely as possible to the 4770T and basically have the exact same chip? There's no voltage information I can easily find to determine if the lower wattage processors are tweaked in any way or whether they're simply taking the 4770K and just configuring it differently hence they'd overclock the same.

 

[Yuriman]

Can someone tell me if Intel's T series processors are different in any other way besides the multiplier and the turbo? Essentially could I purchase a 4770K, change the multiplier to match as closely as possible to the 4770T and basically have the exact same chip? There's no voltage information I can easily find to determine if the lower wattage processors are tweaked in any way or whether they're simply taking the 4770K and just configuring it differently hence they'd overclock the same.

The S and T models also have a lower TDP, so they will throttle if they exceed certain power specifications (and in some cases will not even run at the frequencies advertised). I can't speak for Haswell, but on Ivy Bridge you can't generally set the TDP quite as low as it is on S and T processors, using K chips.

So far as I can tell though, the binning isn't much or any better on S or T chips, so if you run a K chip at the same frequencies, it will produce approximately the same heat, just without the aggressive TDP limits.

 

[Flapdrol1337]

If you underclock and undervolt a K you'll probably get something similar, yes.

If you can cool the K on stock I wouldn't bother even doing that though, a cpu is near idle most of the time, and if you keep the powersaving on there will be no difference in idle powerconsumption, as both go back to a few watts.

Only reason to get a T or S is if the cooling is insufficient for a real cpu due to some extreme small formfactor (intel nuc and such). Otherwise it's just a slower, more expensive cpu.

 

[ElFenix]

S and T parts don't get much review from enthusiast sites (and for good reason) so i have to keep going back to this one:
http://www.silentpcreview.com/article1202-page3.html

basically, because intel's power saving technology works so well, if the parts are running exactly the same load (i.e. the S and T parts are not hitting their thermal wall), the power consumption is the same. when an S or T part hits a thermal wall, the K part could consume more power, but it's also doing more work - so a small undervolt on a K part can make up the difference in power per job (that is, the K part gets done with hurry up and wait sooner, and so returns to idle while the other parts are still at work).

 

[Qwertilot]

Only thing is that that was Sandy. I doubt they've changed they're policy since then but they really have been progressively biasing towards performance in 15-20w power budgets. Quite agressively too.

There's more or less a Haswell i7T (i7-4765T, 35w version, 2 ghz base, 3 ghz boost.) review on the main site here.

Skylake also seems like it might rather up the performance of the T stuff a fair chunk. The leaks - thread here - seem to suggest the i5/7T's might be 2.7/3.5 and 2.8/3.6 boost respectively. Seemingly at 35w, although obviously not at all certain yet.

At some point there's enough performance that the reduced cooling - must be pretty easy to passively cool a 35w max TDP processor - makes it worth it

 

[Insert_Nickname]

Can someone tell me if Intel's T series processors are different in any other way besides the multiplier and the turbo?

Based on a single 4790T I've seen, they have a slightly lower Vcore too.

At some point there's enough performance that the reduced cooling - must be pretty easy to passively cool a 35w max TDP processor - makes it worth it

If we look at pure frequency, you can clearly see a downward trend in required TDP.

The, very popular, Nehalem i7-920 required a 130W TDP to do 2.67GHz/2.8GHz (and needed a 25W northbridge in addition), Sandy Bridge required 65W to do 2.8GHz (2600S). With a pretty large turbo boost of 3.8GHz too mind you. Ivy Bridge lowered to 45W for a 2.5GHz part (3770T), also with a pretty impressive turbo of 3.7GHz. Haswell even has a 35W part (4785T) with slightly reduced frequency (2.2GHz), but again with aggressive turbo (3.2GHz). The 45W 4790T has a 2.7GHz base frequency, and so has a higher frequncy then the previous Ivy 3770T.

 

[TeknoBug]

i7 S and T variants has massive performance per watt ratio, worth it if you're not an overclocker.

My i7 3770K was a silicon lottery chip, I undervolted the bejesus out of it and still was able to overclock it.

 

[ryrynz]

Cheers guys.