Power Supplies (80 products)

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What wattage of power supply do I need?

Each component in a computer will draw wattage from the power supply to run, with the processor and graphics card being the most power-hungry by far. There are ultra-high-end graphics cards out there, like the NVIDIA GeForce RTX 4090, which can pull in excess of 300W alone. In comparison, even the fastest PCIe Gen4 NVMe solid-state drives on the market barely consume more than 10W under load, while you can expect a case fan to use 4W at most.

To determine what wattage of PSU you need, you could manually add up the power consumption figures for each component. Alternatively, and less tediously, you instead could look at your graphics card's spec-sheet, which will almost certainly have a 'minimum PSU recommendation' or similar. This recommendation will be based on a complete system with that graphics card installed, giving you a good idea as to what sort of unit is required. For example, the 'required system power' for an RTX 4090-equipped PC is a 850W PSU, while the 'total graphics power' of the graphics card itself is 450W.

However, you may want to consider buying a PSU that's slightly more powerful than what you need to facilitate future upgrades. Pick up a higher-wattage unit now and your system will be able to support faster, more power-hungry CPUs and GPUs in the future. This will save you money in the long run as you won't have to buy a new PSU every time you upgrade. A higher-wattage power supply will also ensure there's more than enough headroom for all you hardware to run smoothly and efficiently, even in the case of a sudden spike to power draw.

Modular vs semi-modular vs non-modular power supplies

A modular power supply has no pre-attached cables. Instead, all the PSU's cables are included in the box separately, and it's up to the user to attach only the cables they need for their specific build. As you won't have a bunch of extra, unused cables with a modular PSU, it can make cable management easier and help minimise clutter in your system. This comes in handy especially if you're building a cramped small form-factor case.

On the other hand, all the cables of a non-modular power supply are non-removable. Non-modular power supplies are a more budget-friendly option, though they aren't the easiest to work with. If you don't pay close attention to cable management with a non-modular PSU, then its cables can get out of hand quickly.

Then there's semi-modular power supplies. As the name implies, a semi-modular power supply is somewhere in-between a modular and a non-modular unit. They have some non-removeable cables - mostly ones that are essential to a system's function - as well as some removable ones. Semi-modular PSUs are a popular choice as they tend to be a bit cheaper than a full-on modular unit, but you get much of the same benefit as one.

Of course, regardless of whether you opt for a non-modular, semi-modular, or modular PSU, make sure it has enough connectors and cables for your needs.

What is 80 PLUS?

80 PLUS is an efficiency rating system for power supplies. The higher the efficiency of a power supply, the less power it will waste converting AC power from the socket to DC power used by your system. In turn, this will result in less heat, noise, and power consumption.

As you'll see from browsing our range of PSUs, the 80 PLUS system is split into 80 PLUS White, Bronze, Silver, Gold, and Platinum, with White being the least efficient and Platinum the most.

Importantly, 80 PLUS is not a rating of the PSU's quality. It's purely about efficiency. Just because a PSU achieves an 80 PLUS rating does not mean it will be a high-quality unit. An 80 PLUS Bronze unit can be higher quality than a Gold one, for example. That said, you can, for the most part, infer the quality of a PSU though its 80 PLUS rating. More efficient components tend to be of a higher quality, too.

Power supplies at Ebuyer

You do not want to skimp out on the power supply in your system. After all, it's what's connected and delivering power to every component. If something were to go wrong with your PSU, there's a chance it could take out the rest of your system with it. So, whether you're upgrading your PC, building a brand-new one, or looking at replacing an old unit, we stock plenty of high-quality power supplies for you to choose from.

Get your new PSU by tomorrow with next-day delivery, and spread the cost of your purchase with our flexible finance offers.