Power
The output power of the power supply, in other words, is the maximum power that it is capable of delivering to the system. For the computer to operate efficiently, the power supply must be greater than the total power consumption of the system at maximum load. The latter can be calculated by summing the power of individual components, however, in general, for office configurations
, about 400 W —
450 W is considered sufficient, for medium gaming — about
600 W(
500 W,
550 W,
650 W,
700 W,
750 W), and for the top ones —
power of 800 W and above (
850 W,
1000 W and even
more than 1 kW).
Certification
The presence or absence of an 80+ certificate for the power supply. This certificate indicates high energy efficiency: to obtain it, the efficiency (see above) must be at least 80%, and in different modes (20%, 50% and 100% of the maximum load). There are several degrees of 80+:
—
80+. The original version of the certificate, assuming an efficiency of at least 82% (at least 85% for 50% load).
—
80+ White. The second name of the original 80+ certificate (see above).
—
80+ Bronze — efficiency not less than 85% (for half load — 88%).
—
80+ Silver — respectively 87% (90% for half load).
—
80+ Gold — 89% (92% for half load)
—
80+ Platinum — 90% (94% for half load).
—
80+ Titanium — 94% (96% for half load).
The power factor (see "PFC Type") must be at least 0.9 for the lower levels and at least 0.95 for the Platinum level. Also note that for redundant power used in server systems, the efficiency requirements are somewhat lower.
+5V
The maximum current that the PSU is capable of issuing + 5V to the power line. For more information about power lines in general, see "+3.3V". Also note here that + 5V power, in addition to connectors for motherboards (for 20 and 24 pins), is also found in Molex and SATA plugs, as well as some other specific types of connectors.
+12V1
The maximum current that the PSU is capable of delivering to the first power line is + 12V.
For more information about power lines in general, see "+3.3V". Here it is worth mentioning that 12 V is the most popular voltage among computer power connectors. It is used in almost all such connectors (with a few exceptions), and some plugs (for example, additional PCI-E power for 6 or 8 connectors) use only 12-volt lines — and in the + 12V format. And the division of + 12V power into several separate lines is used for safety purposes — in order to reduce the current flowing through each individual wire, and thus prevent excessive load and overheating of the wiring. However, some manufacturers do not specify the maximum current for individual + 12V lines and give only a general value in the characteristics; in such cases, this number is indicated in this paragraph.
+12V
The maximum power that the PSU is capable of delivering to the + 12V power line.
See "Maximum current and power" for details on power lines in general. Here it is worth mentioning that 12 V is the most popular voltage among computer power connectors. It is used in almost all such connectors (with a few exceptions), and some plugs (for example, additional PCI-E power for 6 or 8 connectors) use only 12-volt lines — and in the + 12V format. So this indicator is one of the most important characteristics of any PSU.
Note that many power supplies have several separate + 12V power lines. In such cases, the total power is indicated here, which, usually, is divided equally between the lines.
