Question Why are my motherboard temps and voltages reading 0?

[galennare]

Hi all,

I was recently installing a new PCIe wireless card and I started getting a CPU fan error on boot, and the CPU fan would spin up to 100%. This would obviously prevent me from booting. When I entered the firmware, all of my motherboard/CPU temps and voltages would read 0 or N/A.
Meanwhile, I can manually set the fan speed in the firmware settings. The system will also not POST after trying to boot once, it hangs with the VGA and BOOT error lights on. The only solution to this latter problem I have found is to fully cut power to the system (by turning off the power supply or unplugging it), wait a few seconds, and then try again.
The strange part is, if I "Discard changes & exit" in my firmware settings, I can boot to Windows just fine, and the only difference that I noticed is that the fan is constantly spinning at 100%. While in Windows, I can still see that HWInfo64 displays system temps and voltages properly, so clearly the system can read them just fine, but for some reason the firmware can't see/read them, and therefore thinks there is a problem with the CPU fan?

I've tried the following things:

• Loading optimized defaults
• Hard resetting the firmware (by taking out CMOS battery)
• Taking out all PCI expansions except a single GPU, as my processor does not have onboard graphics
• Unplugging/rearranging all fan connectors

Short of replacing the mobo (which obviously I would like to avoid doing), I am stumped. I use this computer daily for both work and classes, so it would be great if I could get this fixed as soon as possible.

Here are my specs if they are any help:
AMD Ryzen 7 2700x
16GB DDR4 RAM - in dual-channel
1TB M.2 NVMe SSD
1+4TB HDDs
EVGA GeForce GTX 1070 SC - PCIe16_1
EVGA GeForce GTX 950 SSC ACX 2.0 - PCIe16_2
ASUS ROG Strix X370-F GAMING

 

[AlexTheFern]

Have you tried updating the BIOS?

also, not sure if you have yet, but update drivers too

 

[galennare]

Have you tried updating the BIOS?

also, not sure if you have yet, but update drivers too

BIOS is up to date. What drivers could be affecting this? The problem appears before Windows even boots.

 

[AlexTheFern]

In BIOS, try going to advanced mode (by clicking F7 I think)>then monitor>set cpu fan speed from n/a to ignore.

 

[galennare]

In BIOS, try going to advanced mode (by clicking F7 I think)>then monitor>set cpu fan speed from n/a to ignore.

This got rid of the fan error, but if I try to boot like normal, Windows rejects my main GPU (Shows in device manager, but says "Windows has stopped this device because it has reported problems" and has a black screen ).

EDIT: Never mind, I still have to fully unplug and re-plug my system in order to be able to reboot still. Motherboard temps and voltages still read 0 or N/A.