Corsair RMX Series (RM850X), 80+ Gold Certified 850W Fully Modular Power Supply

Bought this to replace an old 650x corsair PS I had in my last build for the current rig. That power supply lasted nearly 11 years people! Sure it was older and not modular as that wasn't a thing - but 11 years? My system is centered around corsair from the cpu cooler, ram, fans, pc case, mouse pad and psu. Everything runs flawlessly, simple to install with a focus on aesthetics and the cable management is insane - especially with that 5000d case.850x is more than I require, but this is also future proofing as I intend to be using this psu for a decade or so. Its fully modular, meaning you can only attach the wires you need, which eases the strain of the cable management chaos. I have 4 cables attached to power the cpu, gpu, sata sdd backups and of course all the rgb modules on the back panel). Great, quiet and modular psu backed by Corsairs legendary quality.

These power supplies are extremely well-built and come with a 10 year warranty. The output is stable with minimal ripple on the 12V rail and acceptable 5V & 3.3V characteristics. Efficiency is on the upper end of the 80+ Gold specification, just barely missing 80+ Platinum. The fan often does not spin at idle and remains extremely quiet even when under near-full load. Coil whine has not been a problem, in contrast to older units. Cables are mostly flexible & easy to route, though the 24-pin ATX connector's capacitors do mildly complicate cable management moreso than with other cables, but do further smooth the output.

I purchased this for a 2014 Dell XPS 8300. Its original PSU was rated at 460 W, but I wanted to go a little higher because I plan on buying a new GPU soon. I've been using this system with the new PSU installed for a week as of writing this review, and so far I'm very happy. The fan works great - it's quiet and when it turns on, it's powerful. It combines well with the case fan. I've had no issues what-so-ever and will be back here to update this review if anything changes.Update (Feb 2020): Still no issues. PSU working just fine. I installed the new GPU (MSI NVIDIA GTX 1660 Ti Gaming X) and believe it or not the system works. Now, the system does experience regular crashes when skipping while watching videos with the new GPU (that's probably due to the the Dell bios not being up to the task). For all other tasks, including kids gaming (Roblox, Minecraft, Fortnite, GS:GO), there have been no issues and the PSU is supplying ample power to the cpu and gpu for this old Dell system. I keep the 5-star rating for this PSU.Update (August 16, 2020)No issues at all. On a related matter, the regular crashes on skipping videos after installation of the new gpu as discussed above have completely stopped for some reason. System is working like brand new, and the PSU is still quiet and efficient. Still happy with this purchase.

Update: 8/15/2021I’ve now had this PSU for nearly 2 years and it’s performed beautifully since the day I bought it. I haven’t had any problems whatsoever.I just got this PSU a few days ago and I really like it. This is an upgrade from my Cooler Master 750W 80+ (non-bronze/gold etc.,) PSU and I’m glad I got it.The all-black cables look really nice and don’t clash with other aesthetics like ketchup & mustard cables on a lot of other lower quality PSUs do.This comes with plenty of cables and I’m not using most of them but it’s nice that they are there.I also think the little bag of zip ties they throw in is a nice touch. I actually ordered a bag of zip ties with this because I didn’t know it came with them and I didn’t even use them because Corsair had me covered.All in all this is a high quality PSU with 80+ Gold certification and 850W which is more than enough to handle almost any system build that a normal, everyday computer will need. It will definitely future proof your system as you won’t have to replace your PSU for a LONG time.Corsair also has a very nice 10 year warranty on this PSU which just goes to show how much faith they have in the quality and durability of this product.