Z440 workstration - Main fan is running fast and constant - not overheated

[freshflyingfish]

Hello

My heatsink fan is running constantly and is really fast and loud. I have checked everything I know how to check. It is not overheated. It is clear of dust. I have plenty of memory. All drivers are up to date and no errors showing in device manager. Nothing crazy in CPU or processes. I am not running any massively taxing programs atm - makes no difference what is running.  I have scanned for malware and viruses- all clear. Recently replaced the clock battery which caused bhioids issues, but they have been resolved. I've had this problem for a few weeks now. It did stop for a while but has just started up again. Could it be the thermostat on the fan? Is there anyway to check? Or maybe old thermal paste?

OS is installed on the SSD. Additional HDD is just for storage. Plenty of space on both. 

Installed a new wifi adapter yesterday, but uninstalling this makes no difference. 

System Name: DESKTOP-12QVTJO

[System Summary]

ItemValue

OS NameMicrosoft Windows 10 Pro

Version10.0.19045 Build 19045

Other OS Description Not Available

OS ManufacturerMicrosoft Corporation

System NameDESKTOP-12QVTJO

System ManufacturerHewlett-Packard

System ModelHP Z440 Workstation

System Typex64-based PC

System SKUF5W13AV

ProcessorIntel(R) Xeon(R) CPU E5-1650 v3 @ 3.50GHz, 3501 Mhz, 6 Core(s), 12 Logical Processor(s)

BIOS Version/DateHewlett-Packard M60 v02.61, 23/03/2023

SMBIOS Version2.8

Embedded Controller Version255.255

BIOS ModeUEFI

BaseBoard ManufacturerHewlett-Packard

BaseBoard Product212B

BaseBoard Version1.01

Platform RoleWorkstation

Secure Boot StateOn

PCR7 ConfigurationElevation Required to View

Windows DirectoryC:\Windows

System DirectoryC:\Windows\system32

Boot Device\Device\HarddiskVolume2

LocaleUnited Kingdom

Hardware Abstraction LayerVersion = "10.0.19041.3636"

UsernameDESKTOP-12QVTJO\james

Time ZoneGMT Standard Time

Installed Physical Memory (RAM)32.0 GB

Total Physical Memory31.9 GB

Available Physical Memory25.0 GB

Total Virtual Memory36.7 GB

Available Virtual Memory29.4 GB

Page File Space4.75 GB

Page FileC:\pagefile.sys

Kernel DMA ProtectionOff

Virtualisation-based securityNot enabled

Device Encryption SupportElevation Required to View

Hyper-V - VM Monitor Mode ExtensionsYes

Hyper-V - Second Level Address Translation ExtensionsYes

Hyper-V - Virtualisation Enabled in FirmwareNo

Hyper-V - Data Execution ProtectionYes

[Hardware Resources]

[Conflicts/Sharing]

ResourceDevice

I/O Port 0x00000000-0x00000CF7PCI Express Root Complex

I/O Port 0x00000000-0x00000CF7Direct memory access controller

I/O Port 0x00002000-0x00002FFFIntel(R) Xeon(R) E7 v3/Xeon(R) E5 v3/Core i7 PCI Express Root Port 2 - 2F04

I/O Port 0x00002000-0x00002FFFNVIDIA Quadro K2200

Memory Address 0xF2000000-0xF30FFFFFIntel(R) Xeon(R) E7 v3/Xeon(R) E5 v3/Core i7 PCI Express Root Port 2 - 2F04

Memory Address 0xF2000000-0xF30FFFFFNVIDIA Quadro K2200

IRQ 17Intel(R) Active Management Technology - SOL (COM3)

IRQ 17High Definition Audio Controller

Memory Address 0xE0000000-0xF1FFFFFFIntel(R) Xeon(R) E7 v3/Xeon(R) E5 v3/Core i7 PCI Express Root Port 2 - 2F04

Memory Address 0xE0000000-0xF1FFFFFFPCI Express Root Complex

Memory Address 0xE0000000-0xF1FFFFFFNVIDIA Quadro K2200

IRQ 18Intel(R) C610 series/X99 chipset USB Enhanced Host Controller #1 - 8D26

IRQ 18Intel(R) C610 series/X99 chipset USB Enhanced Host Controller #2 - 8D2D

[SDH]

In most of the HP workstations there is an ambient air temperature sensor built into one of the front cables. Front because that is where the ambient (external) air temperature can be most accurately determined. It often is encased in a thin heat shrink, and the cable may be zip tied to the front metal of the case at an intake grill. A common cable bundle it is found in is the front ON/OFF switch - front LED activity - maybe front mic/headphone bundle. Here's an example from eBay for the Z440, and the second part number seems to work better. HP parts have a Spares P/N and an Assembly P/N for the same part. The Spares one is what you'd see in HP PartSurfer and the Assembly one is usually on the HP label on the part itself or embossed into the black plastic (that one is easier for a seller to find and list in their ad).

The motherboard self-protection firmware will trigger high fan speeds if it sees too high or too low temps reported from the sensor. HP's Performance Advisor free software is a good way to check that but also you might want to try the free version of HWMonitor from CPUid.com. The HP software can be somewhat hard to find and get working. 

Here's that pic:

This probably will fix your issue...

[freshflyingfish]

Thank you for such a comprehensive and clear reply. I'll try that out and let you know what happens. 

[SDH]

I appreciate that, but there is a problem... my advice is wrong. I looked into this a bit deeper and saw some odd things when I searched for those two numbers. So, I went to one of my two Z440s here and opened it up, and there is nothing that looks like that ON/OFF switch with sensor. I'll take the time to post some pics from inside mine and it may be that the ambient sensor is built into the full front panel I/O assembly. I'll show you the part numbers on mine. Those are available and not too expensive but don't go buy that other one until you take a look yourself at yours and the pics I'll post tomorrow.

You can imagine I've been inside all these HP workstations since the xw era... This will be interesting to get right.

[freshflyingfish]

Thanks again. I haven't bought anything yet🙂. I did manage to find HP Performance Adviser (well buried!). Ran a check but sensors look fine as far as I can tell. See pics. Also tried the CPUID HW Monitor but it doesn't seem to do anything. 

[SDH]

You show 9 degrees C for your ambient (room air) temperature. That is 48.2 degrees F. Is that really the case where you're running that Z440? If the temp is off too high or too low the motherboard will trigger a crisis response. I've seen it happen both ways, but it is more common to falsely read too high. I don't know what the "too low" threshold value is for the MB to trigger.

Well, this was not the first time an eBay ad has been in error. Go look on eBay for the 2 part numbers below:

HP Z440 Workstation Front I/O Board spares 761511-001 assembly 729600-001 4xUSB3 Ports/ON-OFF switch/Front LED lights/Mic & Headphone jacks.

That is what I'm sure you and I have. There are three cables that plug into the rear of that module each having their own part number. One is clearly for front USB3 ports. The other big one is where most of the I/O wires go. The smaller other one is likely for front mic/headphones. I can't find a shrink-wrap-hidden thermistor, but maybe you can.  There is another possibility... instead of a "free-air" version HP may have switched to a "surface-mount" version. That might be inside the I/O module noted above, or even on the motherboard. Take a look at this old post for more on the 2N3904 HP used in earlier workstations: HERE 

These two are supposedly near equivalent except for form factor and attachment:

HP used the free air version earlier including in the ZX20 family

Regarding the free HWMonitor... you are right. It no longer reports fan speeds. It used to. Perhaps it just became too much trouble to integrate all the newer digital sensors in with accuracy. DGroves explained in the past that the sensors put out digital data but that only HP knows the true offsets from that digital output to report reality. That is why HP Performance Advisor is supposed to be the most accurate.

You might want to get a different front I/O module and see if that helps. Those modules are the same for the Z440 and the Z640 and maybe the Z840. Another possibility is that this part of the motherboard's control system has gone bad. I had a Z440 lose function of its top front charging USB port and tried an I/O module replacement (which did not work because it was a motherboard issue). Had to do a MB transplant to fix that. But that is different engineering, and it does not mean there is no failed/failing surface mount mmbt3904 inside the I/O module. HP has used some of the same wiring/colors over different workstation generations. Maybe go try to find a brown/gray pair on the cable's motherboard end... look at the plug with the most wires.

If a PWM fan loses access to its PWM-braking control signals it runs at full 12VDC speed. That could happen from a defect on the motherboard or even in the PWM control part of the fan's circuit board. Maybe start there with a new used equivalent fan from HP if you can figure out which is going too fast. The part number is on the fan's center label.

Certainly, please let us all know if you figure this out!

EDIT: There are many posts on this issue in the forum here, and our search bar above does just an OK job of finding them. Look with Google too. Plus, DGroves has been dealing with this for well over 10 years and has input including to consider putting in a new CMOS battery, resetting CMOS the deep clearance way, making sure to have your memory mounted in the correct order, plus other esoteric potential fixes. This is another rabbit hole to go down. Good luck on your project.

[SDH]

Here are the front and rear pics of the ZX40 front I/O interface module:

Front...

Rear...