Features
Designed for AMD K7 and Intel ATX +12V 1.1 and ATX 2.03 version (Fully Support Pentium 4)
Serial ATA (Advanced Technology Attachment)
W0004R with Active PFC

What is the PFC?
(Power Factor Correction)
Many loads are highly inductive, such a lightly loaded motors and illumination transformers and ballasts. You may want to correct the power factor by adding parallel capacitors. You can also add series capacitors to "remove" the effect of leakage inductance that limits the output current.(Jim Lux -2002).
Non-PFC offers around 0.5~0.6 PF (Power Frequency), 40%~50% power lost.

Active PFC provides more efficient PF(Power Frequency), 0.95~0.99, it means only 1%~5% power has gone.

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