FRONTPAGE Ivy Bridge Temperatures - It's Gettin' Hot in Here

EarthDog said:

You had bet you would be over 125W TDP, I thought you would not be at the clocks listed in your sig. I ended up being correct. BARELY!

Click to expand...

No no no... lol, even at stock its probably using about 160w of power, i don't know what it actually is, i could Google i guess, but i'm pretty sure its around there.

I will try to put it another way, the 1075t / 1090t / 1100t - FX-8120 / FX-8150 all have a 125w TDP, those Thuban and BD's are all identical CPU's, they simply have different (stock) clock settings (as set by AMD in the factory) the lower clocked ones draw less power than the higher clocked ones, again with identical TDP numbers stamped on the box.

TDP is simply a base number, the actual power draw depends on what variant of the CPU you have, in the same way my 1090t will draw the same power as a 1100t if i clock it to the same clocks (3.3Ghz)

Add to that the stock LLC causes the vCore to fluctuate all over the place...

Its a bit like "this is a 125w CPU,- BUT.....Not really!

Any CPU can have this and that writen here and there, doesent mean thats what its pulling out of your PSU.

That's what i'm driving at.

Frakk said:

No no no... lol, even at stock its probably using about 160w of power, i don't know what it actually is, i could Google i guess, but i'm pretty sure its around there.

I will try to put it another way, the 1075t / 1090t / 1100t - FX-8120 / FX-8150 all have a 125w TDP, those Thuban and BD's are all identical CPU's, they simply have different (stock) clock settings (as set by AMD in the factory) the lower clocked ones draw less power than the higher clocked ones, again with identical TDP numbers stamped on the box.

TDP is simply a base number, the actual power draw depends on what variant of the CPU you have, in the same way my 1090t will draw the same power as a 1100t if i clock it to the same clocks (3.3Ghz)

Add to that the stock LLC causes the vCore to fluctuate all over the place...

Its a bit like "this is a 125w CPU,- BUT.....Not really!

That's what i'm driving at.

Click to expand...

I think we said most of that.

Let me clarify as to not sound stoopid!

"TDP is simply a base number, the actual power draw depends on what variant of the CPU you have"

It is not a number pulled out of the etherial plane though. I will make another post.

No....

TDP is the absolute most that any CPU with that model number will draw given absolute worst case scenario for loading at stock settings.
Unless your CPU is the worst leaking X CPU ever, it may well not hit TDP stock.
A 3.3GHz 125W CPU OC'd to the same settings as a 3.4GHz 125W CPU may well use more than 125W of power, because it was binned for 125W at 3.3GHz. It also may well use less if it was a low leakage special to begin with.

What the TDP says is that at stock clocks the CPU will not draw more than that. Doesn't mean it will draw that.
Any OCing and the TDP has just become completely irrelevant as you don't know what the actual base wattage was, and without that you can't calculate the new wattage.

Archer0915 said:

I think we said most of that.

Click to expand...

Thats a relief, i was not at stock in CoreTemp, i was @ 4Ghz, i even rammed up the vCore to 1.4v to see if it would shift from 124w. it didn't, i don't think its reading what its actually sucking out of my PSU.

This is drifitng a bit off topic so I digress after this, but Frakk, go buy a kill a watt meter and see what your system pulls at idle AT THE WALL. Your CPU cannot be using more than your TDP at idle (that makes no sense actually).

The 3770k I have at 3.7Ghz stock volts pulls 138W peak while 100% load folding. I idle on that PC around 85W or so, thats with a pump and 4 fans mobo/ram.

Bobnova said:

No....

TDP is the absolute most that any CPU with that model number will draw given absolute worst case scenario for loading at stock settings.
Unless your CPU is the worst leaking X CPU ever, it may well not hit TDP stock.
A 3.3GHz 125W CPU OC'd to the same settings as a 3.4GHz 125W CPU may well use more than 125W of power, because it was binned for 125W at 3.3GHz. It also may well use less if it was a low leakage special to begin with.

What the TDP says is that at stock clocks the CPU will not draw more than that. Doesn't mean it will draw that.
Any OCing and the TDP has just become completely irrelevant as you don't know what the actual base wattage was, and without that you can't calculate the new wattage.

Click to expand...

Now that makes more sense.
I remember when i first arrived here, you said my CPU was leaky and you would love to get your hands on it to freeze it in your house of CPU horrors.
I'm still trying to determine if it is as you said.
One thing i do know is it runs among the coolest of the Thuban line overclocked at nice low volts (completley stable) check link in sig.
That doesn't look like a leaky CPU to me, unless i'm missing something? it seems among the best Thubans there are.
Do tell

@ ED, have been intent on getting one to satisfy my own curiosity. i just keep forgetting

Per Intel:

The upper point of the thermal profile consists of the Thermal Design
Power (TDP) and the associated Tcase value. Thermal Design Power (TDP) should be used for
processor thermal solution design targets. TDP is not the maximum power that the processor can
dissipate. TDP is measured at maximum TCASE.1. The thermal profile must be adhered to to ensure
Intel’s reliability requirements are met. Note: Different processors SKU’s have different TDP’s. At the
time of this writing, Intel® Xeon® processors for 2 socket servers (5600 series) are available with a
TDP specification from 40W up to 130W depending on the particular SKU1.

Click to expand...

“TDP. Thermal Design Power. The thermal design power is the maximum power a processor can draw
for a thermally significant period while running commercially useful software. The constraining
conditions for TDP are specified in the notes in the thermal and power tables.”
Notes:
- TDP is measured under the conditions of all cores operating at CPU COF, Tcase Max, and VDD at
the voltage requested by the processor. TDP includes all power dissipated on-die from VDD,
VDDNB, VDDIO, VLDT, VTT and VDDA.
- The processor thermal solution should be designed to accommodate thermal design power (TDP) at
Tcase,max.TDP is not the maximum power of the processor.

Click to expand...

http://www.intel.com/content/dam/doc/white-paper/resources-xeon-measuring-processor-power-paper.pdf

Like I said TDP is not what people think.

Intel recently changed their TDP designations to what Archer posted. Previously it was an absolute maximum.
I think AMDs still is.

Bobnova said:

Intel recently changed their TDP designations to what Archer posted. Previously it was an absolute maximum.
I think AMDs still is.

Click to expand...

Yeah you cant compare Intel TDP and AMD TDP. Do notice that the AMD motherboards support 125w or 95w or 65w. I have never seen an Intel board with those limitations.

That's why the IB TDP went from 77w to 95w, Intel rather specifically doesn't want them to exist.

Wait... I thought that Intel stated it still is a 77W part but would like board partners to leave the 95W value there for............?

http://www.nordichardware.com/news/...s-with-95w-tdp-but-uses-a-maximum-of-77w.html

That is correct Earthdog. TDP of IB is 77W. It is marked higher on the package to ensure board designers did not skimp on the power section for z77, then effectively create boards that are compatible with IB but not with SB. Intel did this to control the 3rd party products in the market, and ensure a certain level of expectations/consistency for consumers.

AMD typically contrasts this approach by continuing to offer more freedom for their partners, and I'm not sure if they do this as a competitive advantage, or if its a necessity in order to get partners to play ball with them.

Boards "tuned" for 77 TDP are not compatible with IB, its fairy tale. IB needs even stronger cooling than SB, at least the exactly same level. So thats reason Intel dont want them to mistaken the lower TDP with "lower cooling", its simply not true. When a solution is trying to handle 77 TDP according to the old style, the CPU will be cooled to less. Because its higher density and some other issues (bad dissipation) is not making the matter any easyer than before. It does consume less power, thats the only real advantage. The system may heat up lesser externally but its critical to mistaken it with "lesser cooling demand", thats wrong.

TDP doesnt necessarely mean "power consume", nor does it mean "heat dissipated", its a matter more complicated than that, so i do understand when the stuff is rather a nuissance to Intel. I however do not support bad thermal solutions (in term soldering is better deal, why not doing so?), thats the only stuff i "throw" negatively at Intel, but not the matter about TDP values.

Here is another TDP explanation.

http://en.wikipedia.org/wiki/Thermal_design_power

Thermal design power From Wikipedia,

The thermal design power (TDP), sometimes called thermal design point, refers to the maximum amount of power the cooling system in a computer is required to dissipate. For example, a laptop's CPU cooling system may be designed for a 20 watt TDP, which means that it can dissipate up to 20 watts of heat without exceeding the maximum junction temperature for the computer chip. It can do this using an active cooling method such as a fan or any of the three passive cooling methods, convection, thermal radiation or conduction. Typically, a combination of methods are used. The TDP is typically not the most power the chip could ever draw, such as by a power virus, but rather the maximum power that it would draw when running "real applications". This ensures the computer will be able to handle essentially all applications without exceeding its thermal envelope, or requiring a cooling system for the maximum theoretical power (which would cost more but in favor of extra headroom for processing power).

In some cases the TDP has been under-estimated such that in real applications (typically strenuous, such as video encoding or games) the CPU has exceeded the TDP. In this case, the CPU will either cause a system failure (a "therm-trip") or throttle its speed down.[1] Most modern CPUs will only cause a therm-trip on a catastrophic cooling failure such as a stuck fan or a loose heatsink.

Since safety margins and the definition of what constitutes a real application vary among manufacturers, TDP values between different manufacturers cannot be accurately compared. While a processor with a TDP of 100 W will almost certainly use more power at full load than a processor with a 10 W TDP, it may or may not use more power than a processor from a different manufacturer that has a 90 W TDP. Additionally, TDPs are often specified for families of processors, with the low-end models usually using significantly less power than those at the high end of the family.

The power consumed by a CPU is approximately proportional to the square of the voltage according to Ohm's law:[2]


(where C is capacitance, f is frequency and V is voltage).

[edit] See also

Ivy said:

Boards "tuned" for 77 TDP are not compatible with IB, its fairy tale. IB needs even stronger cooling than SB, at least the exactly same level. So thats reason Intel dont want them to mistaken the lower TDP with "lower cooling", its simply not true. When a solution is trying to handle 77 TDP according to the old style, the CPU will be cooled to less. Because its higher density and some other issues (bad dissipation) is not making the matter any easyer than before. It does consume less power, thats the only real advantage. The system may heat up lesser externally but its critical to mistaken it with "lesser cooling demand", thats wrong.

TDP doesnt necessarely mean "power consume", nor does it mean "heat dissipated", its a matter more complicated than that, so i do understand when the stuff is rather a nuissance to Intel. I however do not support bad thermal solutions (in term soldering is better deal, why not doing so?), thats the only stuff i "throw" negatively at Intel, but not the matter about TDP values.

Click to expand...

The board's CPU power delivery is what wouldn't be up to spec. Much like AMD boards that only support up to 65w, 95w, 125w or 140w CPUs.
Lower TDP = lower power draw.

Another person that delidded an IVY, he did pretty thorough testing with multiple tims at multiple OC settings. In spanish, but scroll down, good chart.
http://foro.noticias3d.com/vbulletin/showthread.php?t=391334

So we have seen several delided Ivy's that got 5-10+C better temps by changing out intels stock tim and replacing IHS when testing in range of 1.2ish vcore, and more with higher vcore. Beginning to wonder if intels secret sauce is some cheap generic non-conductive paste. I never sell anything, too lazy, so when Haswell comes out, going to have to delid mine....but multiple people getting similar results at similar vcore testing...

FWIW, Janus67 and I tested a delidded 3770K with paste and IHS replaced, but only very shortly.

It ran cooler and with more even cores than the other 3770K we compared it to at idle. However under multithreaded load its temperature shot up approximately 40C, while the other 3770K shot up closer to 30C. The load temp readings were about the same for both, just one started out with much lower readings and its core readings were more even.

Under full pot LN2 and 1.8V, the unmodified 3770K ran fine - the delidded 3770K would throttle under load (CPUz would show the frequency dropping, and the score would be bad for the clockspeed).

This is only one delidded/replaced IHS sample however, and we did not delid/replace the IHS ourselves. It looked like a job well done however, you could hardly tell the IHS had been taken off and replaced... So I don't think this example means anything, other than that it might be kinda hard to delid and replace the IHS and get good results.

Our goal at the time was testing 3 different 3770Ks and running them on LN2, so we didn't waste time when one chip throttled - we swapped it out for the other chips. I'll be giving the delidded one another shot to make sure, this was only one mounting and a 15-30 minute test. I expected to see bad contact with the base of the cooler when I unmounted the LN2 pot from the delidded 3770k, however it looked like a perfect interface.

Interesting link at xs regarding intel TIM and different replacements:
http://www.xtremesystems.org/forums/showthread.php?281094-i7-3770K-intel-TIM-AS5-MX4-PK1-LQP-IX


edit: same as a couple posts up....
(sorry i didn't see it.)

My bet is most of the people recommending a delid don't own an IB or at least did not pay for it.