Average Noise
The PSU’s average noise output is low at both voltage inputs.
Fan Noise & Speed Maps @ 28-32 °C – 115V
Typically, for a CWT platform, the semi-passive operation doesn’t last long if you push the minor rails hard, which I do in these tests. Corsair also has the max combined power of the minor rails set high, at 150W, while most modern platforms keep it at 100W, so they have an advantage in these tests. In any case, at up to 550W at 12V, the PSU’s noise is kept below 20 dBA, so it won’t bother you. The PSU exceeds 30 dBA for short periods, and this is close to its full load.
Fan Noise & Speed Maps @ 28-32 °C – 230V
The 230V fan noise profile has some small differences from the 115V one. The semi-passive mode lasts about the same, and the over 30 dBA operating region starts a bit earlier, at 775W vs. 815W at 115V input.
Thank you for the review, Aris. I can’t decide which PSU to buy, the Corsair RM850x (2024) or the Super Flower Leadex VII XG 850W. They are both at the same price in my country. Which one do you think is the better one and you would take?
Another hardware site, LTT, mentions that the previous version doesn’t have UVP but instead “CFP”? Corsair mentions this has UVP (as required by ATX specification), and I was wondering if you test for that?
don’t follow what LTT says, sorry. I can only know what I do in my lab.
This PSU was the worst I’ve bought over 20 years of building PC’s every few years. The cables smelled of cheap plastic, and the unit itself let off a nasty burnt cable smell, neither of which dissipated away after running it for 3 days under a ventilator. Sent it back to the shop, hopefully getting a refund. Not buying corsair PSU’s anymore for a long time.
Weird, we didn’t notice this smell, which might exist indeed in some PSUs.
I sent it for RMA, they replaced it, just now opened the replacement box, the same nasty smell is on the cables on a brand new unit. Won’t even bother installing it, this time will make sure to ask for a refund.
Hey Aris, thank you for the review. After my long research and your articles, I finally bought this product (it finally arrived in my country). Is it a problem if the 3.3V channel drops below 3.2? If it is a problem, what causes it?
weirdingly enough, I just noticed this post. 3.3V rail is not used so hard anymore.