Practical testing …
The installation went absolutely smoothly and in the used Lian Li O11 Dynamic XL ROG there were no problems with the cable lengths.
To check the quality of the power supply, we looked at the voltages in idle and under load with the program HWiNFO, among other things. To be able to stress the CPU and the graphics card separately, we decided to use Prime95 as the CPU stress test and the Heaven benchmark for the graphics card. HWiNFO and Prime95 can be downloaded from our Overclocking Software section.
Testsystem …
Our test system consists of the following components …
| AMD Mainboard | MSI B550 Tomahawk |
| CPU | AMD Ryzen 9 5900X |
| RAM | 32GB (2x16GB) 3200MHz CL16 @ 3600MHz CL16 Kingston Fury Beast K |
| Graphics card | Sapphire RX5700XT Nitro+ SE |
| Case | Lian Li O11 Dynamic XL ROG |
| PSU | Cooler Master XG Plus 650 Platinum |
The voltages …
Before we look at the voltages in detail, let’s take a look at the voltage tolerances according to the ATX specification. These are +/-5% of the nominal value for the +5V and +12V lines, which results in the following limits. The power supply color codes and pin assignments are listed in our forum under PC power supply pin assignment.
| Voltage | Tolerance | Minimum | Maximum |
| +3.3V | ±5% | +3.14V | +3.47V |
| -5V | ±10% | -4.5V | -5.5V |
| +5V | ±5% | +4.75V | +5.25V |
| -12V | ±10% | -10.8V | -13.2V |
| +12V | ±5% | 11.4V | 12.6V |
Idle values …
The system consumes a little over 100W at idle. The voltages we determined are very slightly below the nominal value but within the specification.
Voltages with Prime95 …
To ensure that the Ryzen 9 5900X is also fully utilized, we use Prime95 in the SmallFFT test here. PBO is also enabled. The CPU’s consumption is about 223W. The voltage increases slightly, but remains below 12V within the specification. According to HWiNFO, the total load of the system is a good 460W, whereas the Cooler Master software outputs 377W.
Voltages under full load …
Last but not least, we test our system under full load. We run Prime95 in the SmalFFT test and the Heaven benchmark simultaneously. The system now needs just over 660W, but the power supply remains stable. The MasterPlus+ software and the display output 582W. All voltages remain fully within specifications throughout the test.
How much Euro electricity costs for an economical silent PC or a real gaming monster can be determined with our electricity cost calculator:
Let us now come to our conclusion …