Greetings,
 
I recently purchased an EVGA Supernova G2 850W and I am extremely satisfied with its performance and quality. I use the ECO mode and it is completely quiet. However, last night after I updated my BIOS (could be a coincidence), I noticed a clang sound when I shut down my pc, that was certainly not there the previous days. I was too tired to investigate and even though I thought it came from my pc, I couldn't be sure that it wasn't a spring from my chair or something.
Today, I shut down my pc after 1 hour of use and here it goes that clang sound again.
 
Upon investigation, I found out that when using ECO mode, when the pc is shutting down, the fan takes 1 spin which produces that clang sound (maybe a spring or something). The fan is not spinning beforehand due to ECO mode. If I disable ECO mode, the clang can be heard upon powering on the PC.
 
Shall I be worried? Is it something that can be overlooked? Why does the fan spin for 1 cycle when ECO mode is enabled during shut down? Is it power outtage?
 
I can provide a google drive link that shows what I am describing and you can see it happening at 00:10 - 00:11. It's a bit dark, but if you see carefully, you ll notice the fan taking 1 spin at that moment and you ll hear the clanging sound. drive.google.com/open?id=0B06mSFVYseeYZnVIUm15VVBxc2M (I hope I am not breaking any rules)
 
Build:
CPU: Intel i7 7700k
Motherboard: Asus Rog Maximus IX Hero (Bios version 906)
RAM: G.SKill Ripjaws V series 16GB 3200 MHz
 
EDIT: OK so I contacted the Customer Support. I was told that the clang sound means that probably something hits the Fan on the initial start up and that is a reason to RMA the PSU if I want, however it should not pose a threat to the overall performance of the PSU or the system, so a mild annoyance at worst. Personally, I am OK with that, I still have the 10-year guarantee if something serious comes up. Also, I was told that the spinning before shutting down is pretty normal for all PSUs. I ll keep an eye on the PSU but I think I will not have any issues in the future, related to that spin/sound. Unless you know, whatever hits the Fan, eventually destroys it, so I will RMA it asap :D

Thank you for your answer!
 
How about the spinning, nothing to worry about that 1 spin that happens on shut down? The performance is perfect overall, I just worry if there's some power leakage or something

It didn't do it at first, I think it started after a bios update (2 days after psu installation if I recall correctly). I haven't noticed any problems performance wise though, even though my motherboard has started acting up lately, with weird boot up behaviour sometimes, but I have not concluded if it is an issue with the psu, motherboard or even if my power on button on the case is being caught somewhere on its way up, causing some soft-post or something.

MSim
Fan making that sound is not normal. If your worried, contact evga about it.  You paid good money for a quality product.
 
My EVGA 750W P2 doesn't make that noise.

+1 that sounds odd to me. EVGA will take care of you regardless. Welcome to the forums! 

I would contact EVGA they would be able to help and better to make sure it's normal then have the system run into an issue. I would wonder if it was spinning for the bios to detect fan motion in the PSU fan but it's odd it would make a noise.