Q-Led cpu temp.. but what temp?

[dspazio]

Hello. Long time lurker, first post. First, I want to apologize for my English (not a native speaker).
And here's the question:

I've a maximus VIII hero motherboard paired with a i7 6700k. For those curious, right now I'm enjoying a 4,6 GHz at 1,290 Volts - 0.005 offset on Adaptive mode and LLC 4. At 22C Room temp I'm sitting at 68-70c max core temp (cooled with a H100i V2) when OCCTing for an hour. I'm not a 24/7 user due to time constraints, but it looks stable so far.

As I can remember, when I set Q-led code function to show cpu temp, it showed CPUTIN (socket temp) on motherboard leds, but I'm realizing that my maximus is showing me the "package" temp (or the highest of CPU core temps).

I could not find any document telling me what CPU temp is that QLed function using. Well, am I becoming crazy? probably, but I want to know your op!

Thanks for your time!

[Chino]

If I had to guess, I'd say socket temperature.

[dspazio]

Chino wrote:
If I had to guess, I'd say socket temperature.

If socket temp is equal to CPUTIN that was my same opinion. I'll attach a screenshot after a few minutes of OCCT. That "CPU" labeled temp in HWMonitor, marked in red is the same temp that QLED shows on the mobo. Also, there's a graph of its behaviour over time. It's kind of weird, cause it skyrocket to 60's and after a few seconds of stress testing, it goes to a pretty normal average as you can see on the screenshot. CPUTIN behaves normal, its getting slowly hotter as tests goes on. No surprises here. So no, CPUTIN is not the cpu temp showed on my motherboard. I'm starting to think that something is wrong on my board due to my recent switch to XMP profile. No need to say that I tried to reset BIOS values to default as a test, but no luck, still getting that weird reading.

Maybe I should need to re-flash the last 2022 BIOS or maybe try to update drivers, but I think this is pretty useless since I believe that QLED is not related to windows drivers.

Thanks for your time, and great TUTs around!

[Korth]

Here's a simplified Intel FAQ page and a detailed Intel document about Intel's processor temp monitoring.

Your i7-6700K has a variety of Intel Thermal Monitoring Technologies. One DTS (Digital Thermal Sensor) adjacent to the IHS reports "TCase" (overall package temp, rated max 64C). The four on-die IA-DTSs report the temps "within" each of the four CPU cores. The on-die GT-DTS reports temps "on the CPU cores" of the Intel HD Graphics 530. Two more DTSs are located near the "middle" of the Shared LLC (L3 Smart Cache) segment and in the DMI3 Uncore (DDR4 iMC and PCIe iLC) segment to provide "Thermal Monitor 1" and "Thermal Monitor 2" deltas for an internal thermal monitoring program running in processor microcode - and these two DTSs are apparently "hardwired failsafe dead-man's switches" which cannot be overridden by any off-processor signals or software. The processor also has a variety of "sideband" signals (like THERMTRIP# which can be sent through electrical pins, firmware, or software) which interface directly with the motherboard chipset (an Intel GL82-family PCH part).

I don't know which DTS probes are present and where they are physically located on the MAXIMUS VIII. A DTS can take a variety of forms, ranging from blocky multi-pin ICs to large resistor-like packages to tiny flimsy little slips of foil.
"CPUTIN" is typically surface-mounted on the PCB immediately underneath the CPU socket, sometimes mounted on the opposite side of the PCB.
"AUXTIN" is sometimes surface-mounted on the PCB immediately underneath or in proximity of the main PSU connector.
"SYSTIN" can be anywhere, sometimes adjacent to the Southbridge (if present, lol), sometimes adjacent to the VRMs.

And the famous ROG Chip sitting near the very middle of every ROG motherboard is a mysterious ASUS-programmed ASIC/MCU, it's basically a whole little computer in itself, it might implement more (undocumented?) Asus temp monitoring/control.

[dspazio]

Korth wrote:
Here's a simplified Intel FAQ page and a detailed Intel document about Intel's processor temp monitoring.

Your i7-6700K has a variety of Intel Thermal Monitoring Technologies. One DTS (Digital Thermal Sensor) adjacent to the IHS reports "TCase" (overall package temp, rated max 64C). The four on-die IA-DTSs report the temps "within" each of the four CPU cores. The on-die GT-DTS reports temps "on the CPU cores" of the Intel HD Graphics 530. Two more DTSs are located near the "middle" of the Shared LLC (L3 Smart Cache) segment and in the DMI3 Uncore (DDR4 iMC and PCIe iLC) segment to provide "Thermal Monitor 1" and "Thermal Monitor 2" deltas for an internal thermal monitoring program running in processor microcode - and these two DTSs are apparently "hardwired failsafe dead-man's switches" which cannot be overridden by any off-processor signals or software. The processor also has a variety of "sideband" signals (like THERMTRIP# which can be sent through electrical pins, firmware, or software) which interface directly with the motherboard chipset (an Intel GL82-family PCH part).

I don't know which DTS probes are present and where they are physically located on the MAXIMUS VIII. A DTS can take a variety of forms, ranging from blocky multi-pin ICs to large resistor-like packages to tiny flimsy little slips of foil.
"CPUTIN" is typically surface-mounted on the PCB immediately underneath the CPU socket, sometimes mounted on the opposite side of the PCB.
"AUXTIN" is sometimes surface-mounted on the PCB immediately underneath or in proximity of the main PSU connector.
"SYSTIN" can be anywhere, sometimes adjacent to the Southbridge (if present, lol), sometimes adjacent to the VRMs.

And the famous ROG Chip sitting near the very middle of every ROG motherboard is a mysterious ASUS-programmed ASIC/MCU, it's basically a whole little computer in itself, it might implement more (undocumented?) Asus temp monitoring/control.

So socket temp isn't equal to CPUTIN?:o I'll take a closer look at your links. Looks I need to do further research to understand the picture. Thanks for the answer!

[Korth]

Socket temp is probably equal to CPUTIN. Technically not exactly equal, due to a few millimeters separation between them, but equal enough to make no real difference.

The processor and processor socket are physically largish things, temps will constantly fluctuate within them - at any given moment some pins and circuits continuously cycle electrical power through millions of fast logic gates, while other pins and circuits are "dark" or "cold" silicon which remain completely idle - in practice some parts of the processor or socket will always run substantially "hotter" or "cooler" than other parts, and the "hot spots" are engineered to flow and fluctuate in an attempt to balance thermal/electrical stress loading. (Heat-carrying electron-transfer through copper conductors is slightly slower than the speed of light through solid copper - less than 20cm per nanosecond - and a 1GHz clock means one logic cycle per nanosecond - so a "hot circuit" actually has a sort of geometrically-progressive "thermal momentum" and "thermal latency" as size and complexity increase, Intel is always slowly pushing the threshold just a little further.)

Most temps will be monitored within the hottest critical processor components (like the CPU cores) and by the package DTS - and the "TCase" temp will be an accurate enough measure for almost any practical purpose. Note that the metallic IHS (along with Intel's semi-solid NGPTIM goop) doesn't perfectly conduct heat "off" the processor, its thermal mass also helps "balance" thermal energy across the entire processor package - so again, individual pieces of the processor (and processor socket) might have internal temp variances, but the overall "TCase" and "CPUTIN" measures are sufficient accurate for real-world temp monitoring/boosting/throttling/shutdown.

I don't have a ROG MAXIMUS VIII motherboard. And I'm unwilling to desolder the processor sockets on my ROG X99 mobos. But I've seen takeaparts of another ROG mobo where the "CPUTIN" sensor (a filmy foily coily little thing) was soldered in place over the main PCB and under the processor socket plastics, not quite centered, positioned in proximity to the largest cluster of VCC/GND pins (where one would expect most of the electrical power to flow in/out of the processor).

And thermal sensors are not all created equal. Intel's integrated DTSs appear to be highly sensitive, responsive, fast, and accurate. Motherboard DTSs (and worse yet, user-pluggable temperature probes) are likely less sensitive, responsive, and accurate - they're not going to be superior to readings from "in situ" processor-integrated DTSs, and they're not going to run in firmware faster than CPU microcode nor on memory faster than CPU SRAM cache nor on a motherboard-ASIC faster and more powerful than the socketed CPU, lol. Small variances are unavoidable, expected, and insignificant - even on the most costly top-tier luxury motherboards.