Test Setup

All measurements are performed utilizing ten electronic loads (seven Array 3711A, 300W each, and three Array 3710A, 150W each), which are able to deliver over 2500W of load and are controlled by a custom made software. We also use a Picoscope 3424 oscilloscope, a CHY 502 thermometer, a Fluke 175 multimeter and an Instek GPM-8212 power meter. Furthermore, in our setup we have included a wooden box, which along with a heating element is used as a Hot Box. Finally, we have at our disposal four more oscilloscopes (Rigol 1052E and VS5042, Stingray DS1M12 and a second Picoscope 3424) and a CEM DT-8852 sound level meter. In this article you will find more details about our equipment and the review methodology we follow.

Voltage Regulation Charts

The following charts show the voltage values of the main rails, recorded over a range from 60W to the maximum specified load, and the deviation (in percent) for the same load range.

5VSB Regulation Chart

The following chart shows how the 5VSB rail deals with the load we throw at it.

Efficiency Chart

In this chart you will find the efficiency of TX750M at low loads and at loads equal to 20-100% of PSU’s maximum rated load.

Voltage Regulation and Efficiency Measurements

The first set of tests reveals the stability of voltage rails and the efficiency of TX750M. The applied load equals to (approximately) 20%, 40%, 50%, 60%, 80% and 100%, of the maximum load that the PSU can handle. In addition, we conduct two more tests. In the first we stress the two minor rails (5V & 3.3V) with a high load, while the load at +12V is only 2A and in the second test we dial the maximum load that +12V can handle while load at minor rails is minimal.


Voltage regulation at +12V may be better than 2% but this still is slightly higher than the TX750 V2. At 5V the deviation is under 3% and at 3.3V it's 3.55%. Overall, taking into account the price segment of this unit, we were satisfied by the voltage regulation since two out of the three main rails registered under 3% deviation. Efficiency at lower loads is very good with 87-88%, but with 80% and 100% load, efficiency goes down a bit, which was expected, since this unit is only Bronze certified. A final note on these tests: The delta difference between in and out temperatures on all tests is huge, a clear indication that the quiet fan does its job very efficiently.

Efficiency at Low Loads

In the next tests, we measure the efficiency of TX750M at loads much lower than 20% of its maximum rated load (the lowest load that the 80 Plus Standard measures). The loads that we dial are 40, 60, 80 and 100W (for PSUs with over 500W capacity). This is important for scenarios in which a typical office PC is in idle with power saving turned on.


At low loads efficiency isn't so good. The 80% mark is surpassed only with 100W of load and with 40W load efficiency drops dead low, near to 67%. Since the unit's capacity isn't so high we expected better efficiency readings here but on the other hand the Bronze badge reminds us to lower our expectations.

5VSB Efficiency

ATX spec states that the 5VSB standby supply's efficiency should be as high as possible and recommends 50% or higher efficiency with 100mA load, 60% or higher with 250mA load and 70% or higher with 1A or more load.
We will take four measurements, three at 100 / 250 / 1000 mA and one with the full load that 5VSB rail can handle.


Efficiency at 5VSB is constantly above the recommended ATX readings and in the first two tests is quite high, while on the last two it is fairly good but definitely not among the best we have seen.

Power Consumption in Idle & Standby

In the table below you will find the power consumption and the voltage values of all rails (except -12V), when the PSU is in idle mode (On but without any load at its rails) and the power consumption when the PSU is in standby (without any load at 5VSB).


Phantom power is only a quarter of the ErP Lot 6 limit (1W) so the unit easily meets the afore-mentioned standard.