New to Overclock.net
Join Date: Jun 2013
Location: Bucuresti, Romania
To keep it simple since it seems that we got lost in translation somehow.
I noticed that the Vardar ER line from 2017 were always starting at 100%. At first I thought that it was the MB (the Asus boards do this) but then I moved them to AQ. Unfortunately they behaved the same.
To be able to see if it was the fan itself doing this and not the underlying controller, I disconnected and reconnected the fan while the system was working and the controller was sending the PWM signal that I configured. The Varder ER did the same thing. (the gray Vardar behave as expected, they follow the PWM setting from the beginning)
I then asked the forum if the new line of Vardar EVOs behave in a similar fashion and it seems they do. That is: they ignore the PWM signal for the first few seconds after they receive power and only then they conform to the PWM setting. They do this so they can achieve around 400RPM minimum speed. It's basically an integrated start-boost.
This behaviour, unfortunately, poses some problems when you want to use a capable controller like the AQ:
- you cannot have a passively cooled system when not under load (by using a set point controller without holding minimum speed)
- if you try it, every time the controller sends other PWM signals > 0%, the fans will spin up at full speed thus defeating the purpose of a silent PC (having 16 fans all ramp up is not a beautiful symphony)
- you stress the fan controller outputs unnecessarily. 6 x Vardar at spin up go over 3Amps. If they would have behaved as a standard PWM fan, you could have doubled that number on a single header without any issues.
- the only way to achieve a slow ramp up is to define the fan header as voltage controlled. This way the fans won't have the power to do their start up routine.
As a side note: I've hot swapped fans a reasonable amount of times due to different reasons and I have never encountered a problem (most server platforms use hot swappable fans and the only difference is that they have a slot and guide the fan). 2 things you should mind: properly align the header and plug before connection and plug it quick. It is not the same thing as hotswapping a PCI card, RAM, etc.
If you are worried that something might break doing this, but still want to test the Vardar EVO behaviour, use your MB fan control software and turn off then on the header and see what the Vardar does (under BIOS or OS, doesn't matter)
Last edited by vvv850; 05-07-2019 at 11:58 PM.