[rasz]

>This board has a Fintek F71878AD, a perfectly capable Super IO controller that can read temperatures, control fan PWM, and monitor fan speeds, but MSI just didn't connect it to the board.

is not true. There is a diagram available for this mobo and U32 (F71889AD) is connected over LPC (modern serial ISA version). Its a full Super IO and it cant be _not connected_ as it also provides keyboard/mouse, serial and printer ports.

The problem must lie elsewhere, most likely bad BIOS.

>Here's what I knew:

> Windows can read CPU temperature directly from the CPU's internal thermal diode, completely bypassing the useless Super IO chip.

why not read temperature directly from Fintek using HwInfo?

https://www.hwinfo.com/forum/threads/faulty-sensor-readings-... and yes it also works on 970 https://forum-en.msi.com/index.php?threads/msi-970-cpu-temps...

not to mention MSI Command Center can read those sensors AND set FAN speeds/curves, and most likely also SpeedFan.

> asked LLMs

LLM failed this person :(

[wildzzz]

Yeah I was going to say that the presence of a PS/2 port almost certainly means it has a SuperI/O chip wired up. You wouldn't be able to shutdown the PC without the LPC bus talking to the SuperI/O. MSI just didn't write code to talk to the fan controller or just didn't bother with displaying it in the BIOS config page.

[rasz]

There are multiple pictures of msi 970 master bios displaying temps and fans just fine so it did work at some point in time. Author either updated to some poorly validated bugfix only/beta bios, or maybe wrong bios for the board.

[bobsterlobster]

There's only one page for my board: https://www.msi.com/Motherboard/970-GAMING/support

And I've tried a couple of versions available there. I was even able to find some beta/unreleased bioses that I've also tested. Unfortunately, none of them enable fan control or fix temp & fan speed monitoring.

[toast0]

> Its a full Super IO and it cant be _not connected_ as it also provides keyboard/mouse, serial and printer ports.

Maybe the ps/2 port and serial/parallel ports also don't work? Lots of people use USB for human inputs, and few people use serial/parallel ports, so I wouldn't expect OP to have tested those ports.

They probably work on most boards, just like the PWM probably works on most boards. But his board seems to have a broken trace or a faulty chip.

[bobsterlobster]

Your hunch is correct, I did not test the PS/2, serial or parallel ports, and I'm only using USB.

[toast0]

Might be worth trying the ps/2 port, if you've got something that fits it.

Or loopback on the serial port; just have to enable it in BIOS, don't need a connector or a serial device.

[bobsterlobster]

Will do. Might be worth to look into it a little deeper.

[rasz]

Bios would error out after not being able to initialize PS2 controller.

[bobsterlobster]

Not sure how LLMs failed me, please elaborate.

Also not sure how you found that model number, it's literally an F71878AD, here's proof: https://www.modders-inc.com/wp-content/uploads/image/2015/02... Taken from here: https://www.modders-inc.com/msi-970-gaming-mobo/2/

I can show you a HWiNFO screenshot of it not reading anything off the SuperIO except Chassis Intrusion: https://imgur.com/a/dYPETWz

The only way I can get a temperature reading is off the CPU probe directly, which I am already making use of. As the article covers in later parts, I'm using HWiNFO and/or PawnIO to do exactly what you say (reading off the CPU probe sensor) and feed it into a fan curve, which then sends the appropriate duty cycle to the arduino.

In the BIOS there's no temperature reading, no fan speed display, and no PWM control whatsoever.

So maybe MSI did wire up the SuperIO, I can't say for sure, but they definitely didn't wire up something, otherwise the BIOS could at least control the fans or see their RPM.

And I've also tried with multiple BIOS versions, so it can't be BIOS related.

Some people online had working sensors on their MSI 970 boards, some didn't, leading me to believe it must've been a defective batch where they forgot something.

Image of an MSI 970 Gaming bios where temp and fans work properly: https://forum-en.msi.com/index.php?attachments/msi_snapshot_...

[rasz]

>how LLMs failed me

I assumed LLM gave you or validate the idea one of the biggest mobo manufacturers on the planet didnt wire temp/fan control on their flagship Gaming board?

>not sure how you found that model number

manufacturer diagram of MSI MS-7693 rev 2.0 (970 Gaming) https://www.elvikom.pl/viewtopic.php?lang=en&t=54275&p=21060...

> it's literally an F71878AD

rev 2 specifies F71889AD but Im pretty sure all Fintek F71868/869/870/878/882/889 are more or less compatible https://docs.kernel.org/hwmon/f71882fg.html https://www.linuxquestions.org/questions/linux-hardware-18/f...

rev 4.0 and up do list F71878AD https://www.scribd.com/document/961738196/MS-7693-Rev4-2 https://html.scribdassets.com/5xds0sz8hsgb4iux/images/27-e6d... diagram has all the fans and temp stuff wired up.

Only one pin comes to mind that would break all temp sensors, fans and Voltage monitoring but not ps2/serial/lpt, that pin is 88 analog ground.

>HWiNFO screenshot of it not reading anything

HWiNFO has this "feature" that makes it hide sensors reporting maximum/minimum possible values. HWiNFO considers such readings sign of a missing/broken sensor. Broken analog ground pin on your motherboard would make all those sensors return bad value.

Video of someone running hwinfo successfully on 970 gaming rev 4.x (F71878AD) https://www.youtube.com/watch?v=Wq50OuGC1ys

[bobsterlobster]

I see, I see. That's an impressive amount of digging you did. Thanks for that. Think I could wire pin 88 to ground and basically fix it?

Even if I do get it fully fixed, I think my project could be useful for motherboards that have thermal probes but no PWM.

Real talk though, I'd love to see this MSI board fully operational.

[rasz]

> Think I could wire pin 88 to ground and basically fix it?

I think you could check if the pin is reliably connected to ground.

Did you buy this board already broken? Its also possible someone connecting Fans shorted 12V to Fintek FAN tacho input (two middle pins on 4 pin connector) frying all ADC inputs, in that case only replacement chip would work.

[bobsterlobster]

>Did you buy this board already broken?

Honestly I have no idea what this board has been through before getting to me. It had the PWM/Temp/RPM issue from the moment I got it. Maybe someone did break the chip. I'm gonna look up that diagram and try to see if the pin is connected to ground

[nottorp]

... but he had fun doing it!