TFX is a compact form factor for a PC power supply. Power supplies in TFX format have power
ratings of 300 W, they are more efficient than power supplies in ATX design, to which they are an interesting alternative. Efficiency is 80% at 20% load and over 50% at 100% load. TFX power supplies comply with Energy Starguidelines and have a size of 17.5 cm x 8.5 cm x 6.5 cm. Depending on the version, they are equipped with low-noise fans.