Question 1

Does the PSU CORSAIR 850W RM850x come with a fan control dial?

Accepted Answer

Yes, the PSU CORSAIR 850W RM850x comes with a fan speed adjustment knob.

Question 2

How does the fan speed adjustment knob work? I have never seen a PSU with this feature. Although I haven't been PSU shopping in a good few years now.

Accepted Answer

With the knob 'off' the PSU will not use a fan on boot and the fan only kicks on when whatever smarts in the PSU determine it is necessary.  I am not sure what the thermal limit is, but it won't turn on the fan until the PSU is quite warm.  There is an audible 'click' when the relay turns the fan on at the thermal limit. Personally, I have set the PSU fan to a low level so the fan always runs even if no thermal limit has been tripped.  There is no 'click' of the relay on since it is always on via the knob.

Question 3

Does this power supply unit operate quietly?

Accepted Answer

So far mine has been really quiet.

Question 4

Hi I am looking at the part number CP-9020270-NA CORSAIR RMx Series RM850x I noticed there is no -12 volt rail will this work with my motherboard MSI mpg z490 gaming edge WIFI?

Accepted Answer

go directly to corsair dot com to find your answer.

Questions & Answers