Install back fan / USB power in Standby

[mmg06]

Hi everyone, 

i have an HP Elitedesk 800 G4 SFF. To improve the temperature I ordered an fan for the back of the chassis that is powered by USB. I installed it outside of the chassis and use one of the 6 USB Ports. Until here everything works fine. 

But the point is: 

if the PC goes in the energy saving mode, the fan is still running. Just if I power off the PC, the Fan stops. 

Neither in the windows options, nor the bios seetings I found any option to power of the USB Power on the back. 

Important: I ue the PC as a HTPC right under my TV and use a special USB mouse (remote) to get the PC back if its in energy saving mode. The USB dongle for the mouse is in the front USB Ports and always be working

What options do I have? I want the USB back fan only to run if the PC is really on (and not in energy saving mode)

[NonSequitur777]

@mmg06,

Welcome to our HP Community forum!

What I would suggest you do, is to scratch the USB powered cooling fan, and use a regular 4-pin PWM cooling fan that is connected to your motherboard's PWM power connection using a 4-pin PWM splitter cable. I've had plenty of practice upgrading the HP EliteDesk 800 G3/4/5 SFF platforms, such as this thread: Solved: Upgrading HP EliteDesk 800 G5 SFF Part II - HP Support Community - 8720291:

The advantage of using your motherboard's PWM power connection is that your external fan will not only turn off when your power off your PC, it will also ramp up when things get hotter -and thus provide more cooling when needed.

Kind Regards,

NonSequitur777

[mmg06]

Thanks for the Feedback! Then I will by another fan with that connector! 

A different question to the topic of fans: 

I installed the i7 8700k and ordered (hint from you 😉 ) the bigger fan with the Part Nr.  810281-001

I installed it the way you did with the fan to the backsite of the case. This fans blows the air away from the cpu (to the outside of the case). Should I turn around the fan so it blows the air trough the heat sink? 

What is with the fan on the backsite - should it blow air inside the case or outside?

Thanks in advance! 

Marc

[NonSequitur777]

@mmg06,

It should blow the air out of the case, assuming you got a blow down CPU heat sink/fan combo.

One thing to consider (if you can do it safely) is to mount a top-down cooling fan directly over the CPU heatsink, blowing air in, as I did.

These cooling mods greatly assists in keeping thing cool(er).

Good luck / Viel Glück!

Kind Regards,

NonSequitur777

[mmg06]

thanks again! 

How did you make the mod? did you cut in the case?

[NonSequitur777]

@mmg06,

Yes, I cut into the top panel using a hole saw like this Amazon-Germany purchase example:

Link: https://h30434.www3.hp.com/t5/Business-PCs-Workstations-and-Point-of-Sale-Systems/Upgrading-HP-Elite....

Kind Regards,

NonSequitur777