This PSU is designed in the TFX12V form-factor (Thin Form Factor with 12V Connector) which is optimized for computer cases 9 to 15 liters large. That’s not the smallest, but quite widespread, type of compact computer enclosures.
Compared to the above-discussed PSUs, this form-factor is larger, allowing to decrease the component density or boost the output power. Besides, the Seasonic SS-300TGW has an 80mm fan which is more efficient and less noisy than the high-speed 40mm buzzers.
The Seasonic SS-300TGW has a perfectly ordinary appearance for its class. It has no unusual features like detachable cables or additional vent holes.
In this view we can see a vent grid in the PSU case that serves to exhaust the hot air. Like the above-discussed models, this one has no On/Off switch.
Although this PSU is designed in a rather roomy form-factor, we can see the same platform inside as in the above-discussed Mini 1U products. The only exception is that the cables are not detachable. So, Seasonic has got an efficient platform with power specs suitable for compact computers and uses it in PSUs of different form-factors without much modification.
Thanks to the roomier case, the filtering components near the mains connector are not as close as to each other as in the previous products.
What’s important for our particular purposes, the larger case helped us dismantle the PSU to have a closer look at the compact platform. We just couldn’t do that with the Mini 1U products because we couldn’t reach some mounting screws.
And now we can check out the controller’s chip. It is the half-bridge resonant LLC converter Infineon ICE2HS01G. The 3PCS01 PFC-controller you can see nearby is manufactured by Infineon, too.
Coupled with the Infineon ICE2QR4765 standby controller (the same as we saw in the SS-300M1U and SS-350M1U), we have the same set of controllers as in Seasonic's Gold-certified G series of ATX PSUs.
Like the junior model in the above-discussed pair, the Seasonic SS-300TGW has Rubycon and United Chemi-Con capacitors at the output.
But there’s also a single Teapo capacitor next to the standby source chip.