Corsair RM850x (2023) Review – Solid Choice for a Modular Power Supply

The Corsair RM850x stands out from other power supplies because it’s modular, saving you time when building or upgrading your PC.

You don’t have to go around the back of your computer and disconnect the cables one by one; instead, you can take off the top of the power supply and detach the ones you need to use right away.

At 850 watts, this power supply can handle any current component load. It comes with an 80 Plus Gold Rating, so you know it’s efficient and mighty, but before making a decision, consider reading the in-depth Corsair RM850X review here.

Solid Choice for a Modular Power Supply

The Corsair RM850x stands out from other power supplies because it’s modular, saving you time when building or upgrading your PC.

You don’t have to go around the back of your computer and disconnect the cables one by one; instead, you can take off the top of the power supply and detach the ones you need to use right away.

At 850 watts, this power supply can handle any current component load, and it comes with an 80 Plus Gold Rating, so you know it’s efficient and powerful.

Corsair RM850x – Technical specifications 

Continuous power W	850 Watt
Dimensions	3.39 Height and ‎5.91 Width Inches or 16 x 15.01 x 8.61 cm; 1.66 Kilograms
Box Content	RM850x 80 PLUS Gold Fully Modular ATX Power SupplyATX CABLE 24-PIN (20+4)2 EPS/ATX12V 8-PIN CABLE (4+4)3 PCIe CABLE 8-PIN (6+2)2 SATA CABLE (3 SATA).SATA CABLE (4 SATA).2 PERIPHERAL CAB (4-PIN).FLOPPY DRIVE ADAPTER (4PIN

Voltage Regulation

The Corsair RM850x was exceptionally good when it came to voltage regulation. At no point did our entire load range fluctuate more than 0.1V from its target line, regardless of how hard we pushed it.

Most other P.S.U.s were equally good, but there were a few exceptions (see below). I’m not surprised by these results as most of Corsair’s P.S.U.s has been very good in this regard, and, given my experience with their quality control, even costly ones tend to be pretty solid.

The market has been moving towards tighter voltage regulation for some time now, and it’s nice to see that Corsair has kept up with that trend. The voltage regulation on our 500W sample was also very good at 0.08V, but things changed with our 850W model.

As you can see, its +12V regulation was pretty poor even under typical loads, significantly once we increased it. The +5V rail’s results were slightly better but still worse than average. I say worse than average rather than good because, while Corsair has focused heavily on improving its voltage regulation in recent years, they are still lagging behind most of its competition in terms of quality, you can also check out the best mousepad for gaming.

Ripple and Noise

A slight bit of noise and ripple here and there is generally okay. If you have an abundance of it, then a modular power supply might not be suitable for you. Because many components need only one or two connectors to run, picking up something more in-depth might help save you money in your initial purchase while giving you more options down the road.

If we keep running with our Corsair example, if you buy it with only enough cabling to get everything hooked up immediately, then down the road, your case could get stuffed, and/or maybe there will be an unexpected expansion in your computer hardware needs that would make such an investment worth making.

You can always add on later, but you can’t take it away once it’s been added. This is where modularity comes into play. The ability to pick and choose which cables you want now and which ones you want later makes buying a P.S.U. Much easier in terms of future-proofing yourself. It also saves Cash when first buying so that all your bases are covered instead of having excess cable lying around unused.

Corsair RM850x – Efficiency and Power Factor

The Corsair RM850x is 80 Plus Gold rated, which means it’s designed to be at least 85% efficient at 50% load. The higher your power factor, or P.F., Rating, the more efficiently your power supply converts A.C. power into D.C. power (your computer components need).

A high-efficiency P.S.U. with a high P.F. Rating usually results in lower energy costs and increased safety. The Corsair RM850X has an 88% efficiency Rating and a 0.9PF Rating. That’s pretty good, considering it is not Titanium or Platinum rated.

In fact, no modular power supplies are currently Platinum-rated. But you can still get one close enough to give you excellent performance and save you money on your electric bill over time.

At $140 MSRP, The Corsair RM850X isn’t cheap. But compared to other high-end modular power supplies, it’s not too bad. It’s not even twice as expensive as its closest competitor, The E.V.G.A. SuperNOVA G3 750W ($100).

And you definitely get more bang for your buck with all those extra cables included! For example, The E.V.G.A. G3 only has four SATA connectors, but with all that extra space in your case from having fewer cables in your wiring closet, you can have six cables hooked up to your storage devices!

The only thing I don’t like about The Corsair RM850X is that it doesn’t come with an 8-pin PCIe connector. I understand why they don’t include it since not many people need it nowadays, and most high-end graphics cards, like Nvidia Geforce G.T.X. 10 series and AMD Radeon RX 500 series, can run fine without one.

However, if you have one of those newer graphics cards or a multi-GPU setup, you should ensure you get at least 850W P.S.U. You can always use another power supply in addition to your modular P.S.U if your GPU needs more juice than what your power supply can provide.

Load Testing

The first step in our load testing involves using a D.C. power supply and plugging it into various rails of the P.S.U. We will be stressing each rail with a Thermaltake L5 cooler in P.W.M. mode, which draws between 100-140 watts, depending on fan speed.

We take note of maximum and minimum voltages and amperage readings at several points during both our max-ambient temperature tests and our stress tests. The results are displayed in two separate charts, which can be found towards the end of this review.

With so many opinions about what efficiency should be and what amount of current you need, it cannot be easy to get your bearings.

For an 850W unit like our subject today, anything over 80% efficiency at 25°C and 50% load would pass our test. Results are available in two forms: real-world and ideal. 

This measure determines a device’s actual capability in a situation that may not represent what typical use might be like. At the same time, the other measurement presumes that all D.C. output will come from one source. In practice, we utilize both to take advantage of the inherent benefits each offers. We have also covered the best mechanical keyboards for gaming that you can check out!

Use case of modular power supply. 

How many cables do you have on your computer? One, two, three… if you’re like most people, it’s probably four or more. One on the motherboard to the CPU, one on the motherboard to the video card, one on the video card to the monitor, and maybe another on the video card to some external sound device. And when you go to put all those cables together, they often don’t match up quite right or don’t work well with each other. That’s where modular power supplies come in.

Final Thoughts

Overall, it’s hard to find much fault with Corsair’s RM850x. It delivers on nearly every point while keeping its performance at or near 80 Plus Gold levels with ten years of warranty. For those looking to power a modular setup that can handle high loads, an 850W power supply isn’t overkilling; in fact, you could say it’s under-kill, given how easily it copes with demanding conditions, and I would also recommend using the good gaming monitor if you play a lot, you can also considering our list of the best gaming monitor for under $200