How to choose a computer power supply with a multimeter
Nowadays, the new generation of graphics cards, sound cards, optical drives, hard drives and other accessories are not energy efficient in terms of power consumption. When you fill your brain with your love machine, have you ever thought about equipping it with a strong heart.
There have been many high-level articles on the identification methods of power supplies in various newspapers and magazines. They can be summarized into three types:
Take a look - see whether the power source is made of excellent materials, whether the workmanship is fine, and whether the layout is reasonable. To be honest, this solution is somewhat overwhelming. First of all, it requires the implementer to have sufficient electronic knowledge; secondly, if you want to thoroughly see the internal organs of the power supply, you really have to open the power supply cover, which will inevitably destroy the merchant's warranty seal, which will be automatically lost once the seal is broken. The merchant's warranty means that even if there is a problem with the power supply, you will have to DIY it. I think many ordinary rookies are forced to become prawns in this way when they are desperate and helpless.
The second touch - refers to touching the power supply fan to see if the air blowing out is hot and the cover is hot after turning it on for a period of time.
Three smells: Smell whether the power supply emits a burning smell after working for a long time. The last two are purely the accumulation of perceptual experience. How can a novice make a judgment if he has no experience at all?
Here, I recommend a method to use a multimeter to determine the quality of the power supply, which may provide some help to novices. First of all, of course, find a multimeter (preferably digital), and you must be able to use a multimeter. The voltages provided by the aTX power supply are mainly 3.3V, 5.0V, and 12.0V. 12.0V is the main energy source to drive the hardware equipment. The change will be most obvious after more loads are connected, so after connecting all the loads on the computer Then select any free output head, insert the black test lead into the black wire interface, and insert the red test lead into the yellow wire interface (the purpose is to detect the 12V output voltage). After connecting all the plug connectors, you can start the test.
After starting up, we can find that the multimeter data is constantly changing and does not stabilize until the system is fully started. Write down the voltage value at this time. Normally it should be around 12V (about 11.95V ~ 12.15V). If it is too low, it cannot ensure long-term stable operation of large loads and has no expansion potential. If it is too high, it will cause the device to heat up and cause overheating. premature aging). Then press the rESET key and let the machine restart. At this time, you should pay close attention to the numerical changes of the multimeter. The multimeter value will reach the lowest point during the power-on self-test. Note down the voltage value at this time. If the voltage difference between the highest and lowest voltage is not too large (within 0.3V), this power supply is acceptable. If the voltage difference is too large, it means that the power supply has poor load capacity and should not be selected. I personally encountered a 300W power supply with a maximum value of 12.32V and a minimum value of only 11.73V. It frequently crashed during use.
Finally, observe the situation in use. Run various software and listen to music using the CD-ROM drive to make all parts of the machine work. Pay attention to the voltage at this time and select it if there is no obvious fluctuation.
