ProLiant Servers (ML,DL,SL)

Enable boot without fans on HP DL160G6

Occasional Advisor

Enable boot without fans on HP DL160G6

For a Proof of Concept of an alternative forced cooling system for servers I need to modify a few HP SE316m1 systems. The SE316M1 is also known as SE1120 and is a modified version of the DL160G6. HP part number for the mainboard is: 583736-001.


Main part of this modification is the removal of ALL attached fans.

Before a discussion kicks in on whether I want to do this or not, yes I do. I am providing alternate means of cooling which is impossible with fans attached and working. The hardware is obsolete and therefore warranty issues and potential damage to the hardware are not a problem.

The first problem I encounter is that the systems will not boot with the fans removed.


How can I bypass this safety mechanism? How can I ensure the system will boot regardless of the consequences?

Another potential issue is that (according to the manual) the system performance will decrease with environmental temperatures above 30 degrees C. Since our cooling solution may enable support for temperatures upto 60 degrees,

I would like to know how I can disable this performance decrease . Since I need to test our cooling system, I need to burn these servers to the max to identify potential cooling issues without the system automatically stepping down in performance.


I have no issues with wiring, soldering or chip replacement. Firmware/BIOS/CMOS programming however is beyond my capabilities (except for modifying CMOS values of course:).



Re: Enable boot without fans on HP DL160G6




I do not see a way to override the controls as the BIOS and iLO are inter-related. Sensors embedded in system board at various location detect temperature and the BIOS behaves based on such inputs. 


The server's design ensure that air flow from the fans maintain that the temperature within thresholds. The custom solution that is being deployed may cool the components, but might not effectively clear near the sensors, so the system may not behave as expected. Furthermore, there does not appear to be a thermal sensor map published for this server.


In addition, the system temparature threshold while operating taken from the server's QuickSpecs (DL160 G6) is as follows:


"10° to 35°C (50° to 95°F) at sea level with an altitude derating of 1.0°C per every 305 m (1.8°F per every 1000 ft) above sea level to a maximum of 3050 m (10,000 ft), no direct sustained sunlight. Maximum rate of change is 10°C/hr (18°F/hr). The upper limit may be limited by the type and number of options installed. "


In summary:


Thus what I may say in conclusion is that due to improper airflow along key embedded thermal sensors, the system may be tricked into sensing a fatal thermal event and may not be booting using the custom thermal solution. This behaviour, as far as I know (I may be wrong, please correct me if so, ready to learn!!) cannot be changed.


Hope this helps!!!







I work for HPE
Views expressed herein are my personal opinion and are not the views of HPE

Accept or Kudo

Occasional Advisor

Re: Enable boot without fans on HP DL160G6

Hi Vijayasarathy,


Thanks for the elaborate answer.


Okay, I can work with that. I'll see if I can change my parameters for the testing to keep the temperature below 35 at first. I'll make some effort on localising the sensors and see if I can sabotage them in any way.


The most important issue remains however and involves the removal of all fans. How can I let the system boot without fans being present? Obviously the system detects the connected fans. Any way of fooling the system that the fans are present?




Occasional Advisor

Re: Enable boot without fans on HP DL160G6

I just found this topic on temperature errors on this same system


Apparently the user was able to disable the thermal shutdown protection in some way. Anyone know anything about this?




Occasional Contributor

Re: Enable boot without fans on HP DL160G6


i randomly found this thread when searching for errors on this board.( i'm the author you reffered to in the other post)

Sadly these boards are horrible, i have had two of them fail in 2 years ( the same server even)

If anyone has found a fix to this problem please let me know!

As of your fan issue, there is no way to disable the fans, but you can disable thermal shutdown in BIOS or HPs own configuring software.( i dont remember the correct name but i have the ISO somewhere)

In the meantime i will try to fix the issue, and i will post in on my website.


Occasional Advisor

Re: Enable boot without fans on HP DL160G6

Hi Pappkopp,

Thanks for your response. I already sorted it all, although not easily. The systems in question are actually SE316M1. According to HP, the mainboards are identical to the DL160G6. This turns out to be incorrect, instead the boards are identical to the DL180G6. Regardless, the problems and settings are the same. We have made several PCB's which mimic the fans with a 50hz square pulse from 0-3V. This is the only way to bypass the fan detection.

For the rest, all tests have been successful.

Thanks for the replies!

New Member

Re: Enable boot without fans on HP DL160G6

Hi Aecorsis1,

would you happen to have any circuit diagrams by any chance?