I needed a USB PSU capable of supplying about 85W @ 20V on three separate ports simultaneously (so 255W total). The UGREEN Nexode 300W GaN “Charger” seemed like a good option, as it would have a decent amount of headroom and has a port labeled “140W”, and two “100W”.

However, IMO it’s pure marketing nonsense. First of all, it’s very particular as to what loads you can place on which ports in combination. The only way it can output its rated 300W is if one of those loads is @ 28V. That’s fine, I guess. They can spec it however they want.

These are the various permitted combinations of loads

However, in my testing while loading it with 250W across 4 ports, it started thermally throttling after about 45 minutes. In other words, shutting ports down to save itself from melting down. IMO if it can’t even provide 250W consistently, it should not be sold with a 300W rating. (The testing was performed at about 24°C [75°F], which I think is reasonable.)

In its defense, it does have active PFC and feels incredibly solid. It seemed to be able to provide 200W consistently. But, I would not recommend it unless they change the markings to 200W total and changed the architechure so 200W could be drawn from any combination of ports up to their individual maximum labeling.

While I was searching for a suitable PSU and settling on the UGREEN, I ran across a listing for a “700W” USB-C PSU. Right off the bat, it seemed like an absurd claim. So I purchased it just to take a look and see how much of a BS device it was. It is total crap as one would expect.

Well, not “total” crap. It was able to provide 360W of output for about as long as the UGREEN was able to provide 250W. And it did either thermally throttle outputs (or begin failing intermittently — I’m not sure which) rather than having a meltdown. That being said, the quality of the output was far worse than the UGREEN’s, and it got significantly hotter. (Peaking at about 107°C in one area.) It was untouchably hot after about an hour of loading. Compare that to the UGREEN throttling closer to a 75°C hotspot, and a 65°C average-ish case temperature. (The UGREEN is likely chock full of thermal compound, whereas the 700W no-name had some sparsely strewn about.)

Oh, and the architechture of the “700W” PSU was such that it was essentially 2 completely independent power supplies from the mains to the outputs. So essentially you could only load it to its actual maximum (~360W) by distributing the load across both.

Links to products featured, but this is (obviously) not sponsored, the links are not affiliated, and I don’t recommend you buy either:

UGREEN: https://www.amazon.com/dp/B0DBZY57ZF
700W: https://www.amazon.com/dp/B0CMNQMJ9G

I got this Schaffner NSG 200E Interference Simulator mainframe with an NSG 223A module a while back to test a device featured in a previous video. That was quite a while ago, but I finally got around to taking a look at it.

In this video we’ll check out the device’s internals and power it on for the first time in years. Then test some USB power supplies for interference (spike) pass-through.

The USB PSUs were the cheapest I could find for fast delivery from Amazon, at about 4 bucks each. I wanted them to be of questionable quality, but they seemed surprisingly well-made. Though I’m not an expert, I am a fan of ⁨@DiodeGoneWild⁩ and would love to send these over to him for a more thorough analysis if he’d be interested. (Pre-opened and pre-abused, of course.)

Pictures of the Internals

If you’re looking for a high-power charger/power supply that can also make toast and confections, the SlimQ 330W laptop power supply might be for you! I actually purchased this to use with a Starlink Mini and a USB-C laptop, and it should suffice for that. It seems like a really high quality unit, except that they’re trying to dissipate about 22W of power from this relatively small plastic case (at full load). Though it is around 93% efficient, that extra 7% has to go somewhere.

I had been looking for a cheap and cheerful USB power supply for general charging of phones, tablets, and plenty of etcetera. Hence I ordered this ORICO 4-Port USB Charger with high hopes!

I never have too much optimism when it comes to crap from AliExpress, but not only did this ship from California, it also seems to be a really good buy.

Some of the testing I did on this was inspired by Clive at bigclive.com who does an absolutely obsessive number of teardowns on his YouTube channel. If you haven’t heard of him and you like that sort of this, give it a look! (Plus he has a much better accent than I do.)

And finally, as promised in the video, here are some full-size macro shots of the PCB: