Power Supply
Corsair RM850x 850W 80+ Gold
● In Stock
Price on enquiry · Message us for today’s quote
The fan does not turn at all until the machine starts working for a living. That means the supply contributes precisely nothing to the sound of your desk while you are browsing, writing or watching something, and comes on gently when there is finally a reason to. Behind that sits 850W of Gold-rated output on the ATX 3.1 standard, fully modular sleeved cabling, and a ten-year warranty.
Key Specs
Output — 850W
Efficiency — 80 PLUS Gold
Standard — ATX 3.1, PCIe 5.1 ready
Fan — Zero RPM mode under light load
Cabling — Fully modular
Best for — Idling silently between sessions
Warranty — 10 year manufacturer warranty
What It Pairs With
850W is the right bracket for a Ryzen 7 or Core Ultra 7 alongside a graphics card in the upper-middle of the range, with enough margin left over that the fan spends most of its life switched off rather than merely slow. The ATX 3.1 rating means the unit is built to absorb the brief power spikes a modern card throws at it instead of tripping on them. Fully modular cabling earns its keep in a smaller case, where the cables you leave in the box are the ones you do not have to hide behind the tray.
Who This Isn’t For
A machine with a top-of-the-range card and a processor being pushed hard will keep this unit working often enough that the fan behaviour stops being the thing you notice about it — at that point what you actually need is more wattage, and this is not the unit for that job. It is equally the wrong fit at the other end: a build on integrated graphics or a small card never draws enough to reach the part of the efficiency curve a Gold unit is designed around.
Common Questions
Does a fan that stops really make a difference?
At idle it does, because the supply is often the last thing still spinning. Pair it with a graphics card that also parks its fans at low load and the machine goes genuinely quiet at the desktop rather than just quieter.
Is 850W enough for my graphics card?
It depends on the card and the processor together, not the card alone. Send us both and we will work out the real figure including headroom for spikes, rather than reading the number off a box.
What does ATX 3.1 actually change?
It sets tighter rules for how the unit copes with very short bursts where a card briefly pulls far above its rated draw. A supply built to it is designed to ride those out rather than shutting the machine down.
Check the length of the housing against the space your case allows, and send your graphics card and processor with the enquiry so we can confirm 850W is the right bracket rather than a guess. Availability confirmed at time of quote.