i7 4790k high temperatures ?

70 is great! 85 is even fine for that CPU.

I appreciate your positive attitude.

We live in a technical world where all our gadgets run 24 / 7 on standards and specifications. Since 2007, my goal here at Tom's has been to clarify Intel's temperature spec's for our Forum Members and readers through my Temp Guide, and whenever I can, one thread at a time.

The reasons that most readers find processor temperatures so confusing are; (1) not recognizing the vast number of variables in hardware, environments and test methods which influence temperature measurements, and (2) the glaring lack of clarity within Intel's Thermal Specifications, especially the disconnected relationship between Tcase (CPU temperature) and Tj Max (Core temperature).

Most owners don't know that Tcase is CPU temperature, NOT Core temperature, and that there's a 5C difference which Intel doesn't seem to want anyone to know about, apparently because it provides them with an extra 5C thermal cushion for warranty purposes. Most users don't realize that when Core temperature reaches 100C (TjMax) which is "Throttle" temperature, CPU temperature is right behind it at 95C (Tcase)! Since most users monitor Core temperature and not CPU temperature, I think the fashion by which Intel expresses processor temperatures in their spec's is obsolete.

Unfortunately, Intel currently regards these two specifications (Tcase and TjMax) as separate and discrete entities; one for desktop processors (with Integrated Heat Spreader), and the other for mobile processors (without Integrated Heat Spreader) ... which is confusing for the end user, when we know full well that a defined and documented relationship exists.

Further, I think the fact that the 5C difference between Core temperature and CPU temperature can only be found in a few engineering documents, and is not clearly written into a single, understandable specification, is a HUGE failing. Add to this when you chat online with Intel and ask them about the relationship between Tcase and TjMax, their representatives rarely provide a straight forward and informative answer!

The result is that extremely few Intel owners can make heads or tails out of the woefully lacking, vague, ambiguous and confusing Thermal Specifications. I find it amazingly disappointing that a giant corporation who manufactures and markets the best processors in this world doesn't do a better job of writing Thermal Specifications that are clear and understandable, which apply equally well across desktop and mobile platforms.

If I were to rewrite Intel's Thermal Specifications, there would be no reference to Tcase or CPU temperature. The new terminology would reference Core temperatures only.

The spec's for the i7 4790K would be expressed as:

• TcoreMax 79C: The maximum Core temperature allowed at the transistor junctions within the processor.

• Tthrottle 100C: The Core temperature at which the processor will reduce clock speed for thermal protection.

CT

Well the only time I've seen the CPU hit the high 70's is when I'm running tests made to create heat on the chip. Never in day to day use, which begs the question, just because it can cap at the high 70's does that mean it's not a good overclock, just so long as it's not run in a sustained manner I would think it would be acceptable, not perfect perhaps but acceptable.

Since every processor is unique in it's overclocking potential, voltage tolerance and thermal behavior, I think that whatever overclock you can achieve while not exceeding 1.300 Vcore and 80C is acceptable ... it beats running at stock!

CT

... when I first ran my thermal tests it got as high as 81C on a couple of the cores, but only held like that for 20-40 seconds, then it calmed down to a 76-79C,

Which thermal test? Please be specific.

Small FFT's?

Oh but of course. I just don't like how close it is to 79C, a little too close for comfort.