This category covers PC power supply units up to 650 W for office, home and gaming computers, as well as for upgrading an older system. Most are standard ATX units, with some SFX models and units for server cases. There are over 300 models to choose from, including CHIEFTEC, Seasonic, Thermaltake and DeepCool.
How to choose a power supply up to 650 W
Wattage. Start with the power supply recommendation from your processor and graphics card makers rather than the biggest number on the box. In our range the most common ratings are 650, 550 and 600 W, and there are also 400-500 W units. An office PC without a separate graphics card needs far less, while a system with a mid-range graphics card usually suits 550-650 W.
Form factor. Most desktop cases take a standard ATX unit, and ATX models make up the largest part of our range. Small cases need SFX, while some slim and server cases use PS/2, Flex ATX or 1U units. Check the form factor in your case specifications before buying.
Cabling. Non-modular units, which are the majority in our range, have cables fixed to the unit, so unused leads have to be tucked away inside the case. Fully modular units let you connect only the cables you need, which makes tidy routing easier in a small case. Semi-modular units keep the main cables fixed and make the extra ones detachable.
Efficiency and connectors. An 80 Plus certificate shows how much of the power drawn from the wall the unit turns into usable current: a higher level means less waste heat and often quieter running. Also count connectors: a graphics card needs enough PCIe power connectors, and drives need SATA connectors.
Fan and noise. Most units in our range have a 12 cm fan, and some have 13.5 or 14 cm fans. A larger fan can move the same amount of air at lower speed, so it is usually quieter. Small 4 cm and 8 cm fans are typical of slim and server units.
Brands we carry
- CHIEFTEC: a Taiwanese maker that has long offered both PC cases and power supplies, and it has the most models in this category.
- Seasonic: best known for power supplies, which it also builds for other computer hardware companies.
- FSP and Fortron: Fortron is a brand of FSP Group, so both come from the same power supply manufacturer.
- Thermaltake: known for gaming cases and cooling, and it makes power supplies for the same enthusiast builds.
- DeepCool: mostly recognised for CPU coolers and cases, and it also offers power supplies.
- SilverStone: one of the best-known makers of small SFX power supplies and compact cases.
- Gigabyte: better known for motherboards and graphics cards, so its power supplies are easy to match with parts from the same brand.
Also in our range: Inter-Tech, Xilence, LC-Power and Gamemax.
Frequently asked questions
Is a 650 W power supply enough for a gaming PC?
For many gaming PCs with a mid-range processor and graphics card, 650 W is enough. More powerful graphics cards need more, so check the recommended power supply rating from the graphics card maker first.
What is the difference between modular and non-modular power supplies?
Modular units have detachable cables, while non-modular units have them fixed permanently. A fully modular unit lets you detach every cable, a semi-modular one only some of them. Cable layout and airflow inside the case usually improve, but performance is the same.
Will any ATX power supply fit my case?
Most standard cases take ATX units, but not all do. Small cases need SFX, and some server or slim cases use PS/2, Flex ATX or 1U units. The exact form factor is listed in the case specifications.
Does a higher-wattage power supply use more electricity?
No, a computer draws only as much power as it needs. The rating shows what the unit can deliver, not what it consumes. A very large unit can be slightly less efficient in a lightly loaded PC, so it is sensible to choose a rating without excessive headroom.
