As we have mentioned in other articles and reviews, the first place we look when opening a power supply for a hint about its quality is its filtering stage. The recommended components for this stage are two ferrite coils, two ceramic capacitors (Y capacitors, usually blue), one metalized polyester capacitor (X capacitor), and one MOV (Metal-Oxide Varistor). Very low-end power supplies use fewer components, usually removing the MOV and the first coil. 

This power supply has all required components plus one extra X capacitor, four extra Y capacitors, one extra coil and one X capacitor after the rectification bridges. The MOV is behind the fuse and can’t be seen in Figure 8.

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Figure 7: Transient filtering stage (part 1).

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Figure 8: Transient filtering stage (part 2).

In the next page we will have a more detailed discussion of the components used in the Thermaltake Toughpower XT 775 W.