A good computer needs to choose a suitable computer power supply in order to better play its cost performance. The choice of power supply is generally based on the power of the power supply. Add the power consumption of all the hardware of the computer to get the total power, and then buy a power supply that exceeds this total power by 30%. Of course, buying some brands is more stable, usually the higher the price of these brands, the better the stability. In addition, consider that the heat dissipation of the computer power supply must be good, and see if the heat dissipation process is done well.

  Now the hardware performance is getting higher and higher, and its relative power consumption is getting bigger and bigger, but don't affect the performance of the hardware or simply cause crashes and other troubles because of your insufficient power supply. Therefore, when selecting a power supply, there should be room for the power of the power supply. It is best if the power of the power supply exceeds 30% of the total power of the computer.

Power of main computer hardware:
CPU power: 73W such as mainstream CPU I3 530
Motherboard power: generally 20~30W, integrated graphics is calculated at 35W, generally not more than 40W.
Graphics card power: Generally, the power of ordinary graphics cards is about 60W. Nowadays, the power of many high-end graphics cards is between 120~350W, which requires specific analysis.
Hard disk power: The hard disk power is usually between 10W and 30W, and it is more appropriate to calculate by 30W.
Optical drive power: DVD-ROM drive 25W, DVD-RW / DVD+RW drive 33W.

Therefore, it is more appropriate to choose a computer power supply of 350W and above.

Computer power reference:
Meji Computer Power Saver 420T: rated power 300W, maximum power 420W.
Meji Computer Power Saving King 500T: rated power 350W, maximum power 500W.