Seasonic SS-350TGM TFX 350W Power Supply

We’re looking at something a bit out of the norm here today, a tiny little TFX form factor unit from Seasonic. It’s an 80 Plus Gold 350 watt unit that promises some big performance out of a package smaller than one of my size 14 shoes. Let’s see if Seasonic brought their usual bag of awesome tricks to this party.

PROD LINK: Seasonic’s Current TFX Offerings
PRICE: $69.99 @ NewEgg
Price is at the time of testing!

Wow, it’s been a while since we saw one of these in the lab, hasn’t it? Today, I’m looking at a new TFX form factor unit from Seasonic, the SS-350TFX. It’s been around five years or so since we looked at our last Seasonic unit in this form factor, so it’ll be good to see if these are still fantastic little units like that one was. Man… that review is so old I was still doing an aesthetics score.

At any rate, times have changed and units are expected to be higher efficiency than ever. This one comes in at 80 Plus Gold. Let’s find out how it does.

Of course, we are going to take a look at some of the box marketing first. Five-year warranty? That should be more than enough time, there. 80mm ball bearing fan? That could get a mite loud… we’ll have to see. Semi-fanless operation? I’ll have to check and see where the fan kicks in come load testing time.

This being a Seasonic, we have high expectations for this unit. All that bragging about tight voltage regulation will have to mean something later.

Other sides of the box also have some marketing. This one explains what 80 Plus Gold certification should do for us, as well as telling us it’s ready for Energy Star. Which is kind of the same thing as 80 Plus, only started by the EPA as a more worldwide thing concerned with the energy consumption of stuff in all operation modes, not just when the main power is online like 80 Plus.

However, your power supply must be 80 Plus Bronze or better to even qualify for Energy Star, so the two of them do go together.

And here we have a list of specifications and connectors. I’m not seeing a thermal rating for maximum power, so I’m hoping we’ll find that information in the user guide.

Finally, in case you don’t speak English, the marketing is repeated on this side in seven different languages. No Kaixana, Klingon, or Imadethisoneupa sadly.

Ah, that must be the user guide right there. Let me just unpack so we can see what’s in the rest of the box first.

We have a power supply, a power cord, some modular cables, a user guide, and a warranty guide.

I scanned the pair of these together because together they almost make half a proper user guide. I did not find any indication of a maximum safe operating temperature in here, nor did I find that info online. Looks like we’re going for fifty degrees today if we can get there on such a small unit. That’s my automatic target when I can’t find that data.