Post error 519-Aux fan not detected

[Zolp]

I haa an Z4G5 w5-2445 / 64 Go Ram

I have put an Nvidia 4080GTX who has 3 huge fans. Card is big.

I had remove cooler

Each time, during boot process.... Bip. Aux fan not detected.

for sure, they are on my desk ^^

I have never had cooling issue even on heavy load

I hope that in a near futur they will let the possibility in the bios to switch of warning

[SDH]

In the BIOS of some prior HP workstations there was an option to bypass recoverable errors... the ones that are not fatal, and which you bypass by hitting the F1 key. Below is what that looked like and the default from the factory was Disabled. Here that option has been changed to Enabled. The pic shows the navigation to that BIOS setting:

The Z4 G5 is so new that I could not find a technical and service PDF manual to look up the motherboard position for attachment of the dual-fan device that would compensate for the video card "overcurrent" detection error... that error message might not truly be necessary, and it clearly is a "recoverable error" because the BIOS lets you hit F1 and keep working. Where might that header be on your motherboard? I can't find one on a Z4 G4 motherboard manual so it might be added on to the Z4 G5 motherboard.

EDIT: It will be a 6-pin header on the motherboard... see the picture below, next post, showing the special non-standard cable that goes from the motherboard header to the two-fan PCIe area cooling device.

Here are two options for how to handle this issue:

Preferred Option 1:

Do the same thing the old type of BIOS allowed with your much newer BIOS... I may have found the BIOS setting for that in the Z4 G4 technical manual which I believe will also allow you to bypass your recoverable error issue in your Z4 G5. Please try it and let us know if this works for you. This option should result automatically in the equivalent of you physically pushing the F1 button each time:

Less Preferred Option 2:

This type of issue usually will demand both the front cooling kit and that rear dual-fan cooling kit. Search for those two 7 alphanumerics in the 11/23 QuickSpecs v17, attached below (and there is some added info in there).

AMO kit 56Q84AA = HP Z4 PCIe Retainer with Fans (2 small fans adding air flow to the PCIe area)
AMO kit 56Q79AA = HP Z4 Fan and Front Card Guide Kit (1 larger case fan)

HP traditionally has used PWM fans for such duties, with standard PWM pinouts. The HP plug end may be slightly different from the usual but I've always been able to get a non-HP type plug to fit. Buy a little Noctua PWM fan or plug any PWM fan onto the motherboard header intended for that "PCIe Retainer with Fans" device to test. That will spoof the motherboard if it sees "Sense" ("Tach") activity coming back from the rotor's PCB to the motherboard via pin 3 from that header. You don't need to know the details but any 12VDC PWM fan attached should work. I'm assuming that the two fans on it are wired in parallel so only one united fan plug ends up going to one standard HP case fan 4-pin header on the motherboard. You can Velcro the fan some safe place inside.  I personally would try option 1 and stop at that but watch for overheating carefully when you push the system the first few times.

I'd expect a BIOS update pretty soon to solve this issue if it really is not a problem.

[SDH]

Well, it looks like option 2 is not viable. I found 2 pics in HP PartSurfer that show the device, and also shows a non-standard cable that feeds the device for the Z4 G5. The same cable is used with a different similar device for the Z6 G5. Below are those two pics for the Z4 G5. Note that the white plug is for a 6-pin motherboard header. The black plug has only 3 wires and thus there is some magic going on inside the sheathing from white to black. Spoofing likely is possible if you know what is going on inside that cable but if it was me I'd at least consider getting this kit. HP appears to have done some real engineering/fabrication work on it:

Also, there is a bit more information from Barco about these workstations throwing that error when using the special Barco medical imaging video cards, and they state the error message will be generated from any video card that is not known to the workstation:

HP Z4/Z6 G5 workstation is getting'519-Aux fan not detected' POST errors on the boot up - Barco

Hopefully option 1 in my post above will work... at least this is on HP's radar.

[SDH]

Found a review of the HP Z4 G5 which included an inside image showing the bottom edge of the new motherboard. It shows the white 6-pin motherboard header there... where the special cable shown in the post above is to be plugged into. Note the perforations along the bottom of the case to allow new airflow in from below, either passively or actively via the optional 2-fan device shown also in the post above:

Plug the 6-pin cable in here...