Seasonic SSP-350GT Review

[c_hegge]

I noticed a small error in the spreadsheet I use for calculating the total load. After I modified it to suit the new load tester, I accidentally left out the 5vsb rail from the total, which meant that the PSU was always under about 5W more load than what the table stated. I have corrected the error, and now the efficiency easily clears 80plus gold. I have given back the half point and given the unit a gold award.

[LongRunner]

I don't think you understand LLC resonant topology. The transformer is used symmetrically (the primary side of LLC resonant is actually closer to the old half-bridge topology than anything else), and has a center-tapped secondary. Unlike the other topologies, there is no mag-amp coil.

It's obvious from looking at the solder side of the board that each 12V MOSFET is in parallel with the adjacent rectifier. (This PSU actually has the center tap going straight to 12V and the MOSFETs and rectifiers to ground, possibly because it was easier to lay out that way. The metal thing between the polys on 12V is a conductor, not a heatsink. And the lone rectifier on the solder side is for the 5VSB.)

Also, why didn't you test the -12V to the rating???

[c_hegge]

I don't think you understand LLC resonant topology. The transformer is used symmetrically (the primary side of LLC resonant is actually closer to the old half-bridge topology than anything else), and has a center-tapped secondary. Unlike the other topologies, there is no mag-amp coil.

It's obvious from looking at the solder side of the board that each 12V MOSFET is in parallel with the adjacent rectifier. (This PSU actually has the center tap going straight to 12V and the MOSFETs and rectifiers to ground, possibly because it was easier to lay out that way.

You are correct. For some reason, I under the impression this was a forward converter. I have fixed that bit.

The metal thing between the polys on 12V is a conductor, not a heatsink. And the lone rectifier on the solder side is for the 5VSB.)

I know. When did I say otherwise?

Also, why didn't you test the -12V to the rating???

We all know what was gonna happen. It would have had worse ripple. Besides, it doesn't get used much these days.

[LongRunner]

[The fan] was extremely quiet at light loads. It first became noticeable with the power supply at 250W load, and became fairly loud at full load.

For a small 80 Plus Gold unit, in a cool environment, I take that as being not very quiet at all. I suspect it has something to do with the small heatsinks, and something to do with the big-PSU-fan BS. Several larger/less efficient units on this site are mentioned staying quieter for longer.

[c_hegge]

I agree. I also think that the fan curve is a little more 'aggressive' than some. I don't remember it actually getting that hot. My guess is that it would have done OK even if the fan hadn't ramped up as much.

On a side note, I used this PSU on a Core i3 build with integrated graphics (which is probably more or less its target audience, judging by the lack of a PCIE connector). The fan never became audible.