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.

On this stage this power supply is flawless, providing two extra Y capacitors, one extra X capacitor and one extra coil. This power supply has two MOV’s, located after the rectification bridge. The components used here are identical to the ones used on Huntkey Green Star 450 W.

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Figure 6: Transient filtering stage (part 1).

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Figure 7: Transient filtering stage (part 2).

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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 Dynex 400 W.