have just bought one of those machines and the standard BIOS is of little use regarding fan management as it just shows enabled or disabled fan control:
according to speedfan it sets 30% for sysfan and 47% for cpu fan as minimum level up to about 70 C
is there any chance of "discovering" how to access the advanced BIOS features to lower cpu fan cycle down at 30/35%?
attached both .rom and .upd BIOS files
Thanks in advance
D2990-A3.zip (4.5 MB)
Sysfan may not be adjustable, but I see in your BIOS, this could be adjusted which affects CPU fan speed for sure and changing these may also affect the other fan too but I’m not sure
Since you are talking about lower temps/idle temps, you would need to adjust Passive trip points TC1/TC2/TSP, but you’d have to read about those to see what is ideal settings.
I think there is a big throttlestop thread on some forum which explains all this, but you’d have to find it in google because I don’t remember where it’s located.
What happens if you disable Fan control? This is Disable/Enable of TCV settings, some temp control in that TCV module mentioned above.
This may be in BIOS, I didn’t spot with a quick look, or may be in EC FW on another chip.
There is no additional settings hidden form you on that page
I previously had a look at those values, but there is still something missing (it’s probably something hidden in the TCV module).
disabling TCV will set both CPU and Sys fan to max speed (above 4k rpm).
with TCV enabled both fan speed is constant below 71 C . it is this constant speed that needs adjusting for CPU fan as it is set to 47% (1800 rpm).
Sys fan is set to a more relaxing 1000 rpm (30% for the specific fan) and setting CPU fan to 37% will achieve the same speed (1k).
so there is nothing wrong with the BIOS as it is, it is just a matter of editing the TCV module.
Yes, I assume it is, since that is what’s controlling the fan curve right now. I know nothing about this TCV module, I found some corporate tool for Fujitsu to modify whaever version TCV they use, but I was not able to find a working download for it (or a password for what I could download)
Does it change at 55C, from idle/lowest value, or is it always same from 0C to 71C?
If I know what module was TCV in the BIOS, I could possibly find and edit these values, but I haven’t a clue and searching for TCV in UEFITool either way only brings up the BIOS settings.
no changes at 55C. fan speed is rock solid from 25C to 70C, for both CPU and sys fan. from 70C it climbs up and steps down every 0.5 C.
Never managed to reach 73C even with prime95 running and the case covered in cling film.
still struggling to manage the CPU fan speed… 
Email Fujitsu and see if they will send you a TCV Tool, or tell you which module/GUID is the TCV module, or maybe even send you custom BIOS with TCV adjustable or at least more/actual fan adjust-ability.
Sometimes companies help with special request, just have to ask nicely.