To put this notebook power adapter to a test we used the Coolermaster PSU test-lab in Venlo (NL), for more info about the test setup I'll link you to a previous article where we made some in-depth PSU tests using the same equipment. Although we did add one of CoolerMaster's own PC power supplies in this article you must know at all times that we did our tests on our own according to our specs and requirements with little or no help from CoolerMaster supervisor René. Our result are not biased, our goal is to give facts, not to make advertisements.
Apart from using these industrial test devices we also made a real-life test using an Acer Aspire 5630 notebook where we also monitor the temps. More info later, on to our test candidate ->
Using the Chroma electronic load we set the current draw so that we got 20, 50 and 100% load condition for the 19V notebook charger. Our results:
(left: input power, middle: volts/ampéres, right: output power, most right: efficiency)
In a bar graph view
Efficiency is right where it should be, in high '80s and even over 90% near full load. With 91W power draw we have 100W input power, ie 9W goes to the power consumption of the USNA 95 adapter which translates into only a minor amount of heat generating.
Nevertheless we put the adapter to a real life test, my notebook is rated 19V 4,75A so its the perfect match for this power supply. First I used the USNA 95 for roughly 1 hour to let it heat up a bit, after that I disconnect the unit so that my portable was running on batteries only. Using benchmarking tools I now began draining empty the battery and after my portable has shut itself down I hooked up the USNA 95 again. Once back into windows I again stress tested my portable, this to higher the DC power load because now the USNA 95 is not only charging the battery, it will also deliver enough power to keep the portable running on full load. This way I'll put maximum stress on the USNA 95, I used a Velleman DVM8810 IR temperature meter to monitor the temperature of the housing:
The hottest spot went up to 44°C which is far from being troublesome, you won't actually notice much of a difference when the laptop is being idle or fully loaded. What we can conclude from this graph is that the compact size is not limiting the output power and temperature wise you'll find this adapter radiating roughly as much heat as the conventional laptop adapter/charger.