Removing the top cover is as easy as undoing four screws. One is hidden behind the warranty sticker, which means Seasonic will know that you've opened up the power supply if you try and return it. The 120mm ADDA AD1212MB-A71GL 12V fan is detachable and can be replaced quite easily if its bearings eventually dry up and the impeller seizes. The fuse is not user replaceable.

In the motherboard world, capacitor reliability has become a worrisome issue for many users. A couple years back the whole leaking and exploding electrolytic capacitor issue wreaked havoc, and continues to this day to show its bulging, bursting, electrolyte leaking face on older motherboards. If you've ever had weird computer instability problems all of sudden, odds are good it's a burst capacitor.

It is hard to say how much this issue impacts power supplies, but as motherboard manufacturers are buying millions of the conductive polymer aluminum solid capacitors (a more reliable part at elevated temperatures), the price had come down enough that power supply vendors can utilize the technology has well.

Seasonic utilize one conductive polymer aluminum solid capacitor for the 12V rail on the S12 II. It claims this will deliver higher voltage stability and reliability in the long term. If true, it could yield better performance to enthusiasts overclocking their PCs. Whether this truly makes a difference we're not sure.... but using higher quality components is a positive aspect. The remainder of the capacitors in the S12 II range in manufacturers, but of note is one Japanese made Rubycon.

Power load tests are up next.