This category covers small-format SFX and TFX power supplies for mini-ITX builds, slim desktops and compact cases. It suits anyone building or upgrading a small PC where a standard ATX unit will not fit. Brands in our range include LIAN LI, GAMEMAX, CHIEFTEC and ASUS.
How to choose an SFX or TFX power supply
Form factor. SFX units are small, squarish boxes used in most mini-ITX cases. TFX units are long and narrow and are made for slim desktop cases. Check your case specification first, because some cases need a longer SFX-L unit or accept only one of the two formats.
Wattage. Add up the demand of the processor and graphics card, then leave some headroom. The graphics card is usually the biggest load, so check the power recommendation from its manufacturer. Also confirm the connector it needs, whether that is standard PCIe 8-pin or the newer 16-pin type.
Connectors. Small builds use fewer drives, but the count still matters. In our range the number of SATA power connectors runs from 2 to 6, and 4-pin Molex connectors from 1 to 4. If you plan several SSDs, hard drives or older fans and lighting controllers, pick a model with enough of each.
Output on the 3.3V and 5V lines. Drives, USB ports and some motherboard circuits draw from these lines. Combined power on +3.3V and +5V in our range is most often around 110 W, with some units rated from 85 W up to 180 W. A busy storage setup benefits from the higher figures. The +5Vsb standby line is typically 2.5 A, with some units at 2 A or 3 A.
Noise and cabling. A small unit has a small fan, which often spins faster under load than the larger fan in an ATX model. Look for an efficient design and, if airflow in the case is tight, modular or flat cables that are easier to route.
SFX and TFX power supply brands we carry
- LIAN LI: known for aluminium PC cases, and the brand with the largest number of power supplies in this category.
- CORSAIR and SILVERSTONE: both have long-running SFX lines, with CORSAIR offering its SF series and SILVERSTONE its SX series.
- CHIEFTEC: a long-established maker of PC cases and power supplies, with compact units for small builds.
- ASUS: offers power supplies alongside its ROG and TUF Gaming motherboards and graphics cards, which makes matching a gaming build easy.
- FSP: a major power supply manufacturer that also builds units for other brands.
- STREACOM: known for fanless, passively cooled cases and components for silent PCs.
Also in our range: GAMEMAX, TACENS and AKYGA.
SFX and TFX power supplies: frequently asked questions
What is the difference between SFX and TFX?
SFX and TFX are different physical sizes of power supply. SFX is a compact, roughly cube-shaped unit, while TFX is long and thin to fit slim cases. Both deliver the same kinds of connections as a full-size ATX unit, so the choice depends on what your case accepts.
Can I use an SFX power supply in an ATX case?
Yes, usually, with an adapter bracket that lets the smaller unit mount in an ATX position. Check that the bracket suits your case and that the cables reach your components. A TFX unit generally cannot be used this way.
How many watts do I need for a small PC?
It depends mainly on the graphics card. A mini PC with integrated graphics or a modest card needs far less than one with a high-end card. Add up the processor and graphics card requirements, then choose a model with some headroom above that total.
Are SFX power supplies as good as ATX ones?
Quality depends on the individual model, not only the size. SFX units follow the same electrical standards as ATX units and many handle demanding hardware. The main trade-off is a smaller fan, which can be louder under heavy load, so check the cooling design and efficiency rating.
