Efficiency
Efficiency, in this case — the ratio of the power of the power supply (see "Power") to its power consumption. The higher the efficiency, the more efficient the power supply, the less energy it consumes from the network at the same output power, and the cheaper it is to operate. Efficiency may differ depending on the load; the characteristics can indicate both the minimum efficiency and its value at an average load (50%).
It should be noted that compliance with one or another level of 80PLUS efficiency directly depends on this indicator (for more details, see "Certificate").
Fan size
The diameter of the fan(s) in the power supply cooling system.
The large diameter allows to achieve good efficiency at relatively low RPMs, which in turn reduces noise and power consumption. On the other hand, large fans are more expensive than small ones and take up a lot of space, which affects the dimensions of the entire PSU. We also emphasize that a small fan is not yet a sign of a cheap power supply — quite advanced models can also have such equipment, in order to reduce dimensions.
As for specific diameters, the smallest value that can be found in modern consumer-grade PSUs is
80 mm. The most popular option is
120 mm, this size gives good efficiency and a relatively low noise level at a reasonable price and dimensions. Larger diameters are somewhat less common —
135 mm and
140 mm.
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.
ATX12V version
A standard for power supplies that supplements the ATX specifications regarding power supply along the 12 V line. Introduced into use since the time of the Intel Pentium 4 processor. In the first series of the standard, the +5 V line was mainly used; from version 2.0, the +12 V line was introduced to fully power the components computer. Also in the second generation, a 24-pin power connector appeared, used in most modern motherboards.
SATA
The number of SATA power connectors provided in the PSU.
Nowadays, SATA is the standard interface for connecting internal hard drives, and it is also found in other types of drives (SSD, SSHD, etc.). Such an interface consists of a data connector connected to the motherboard, and a power connector connected to the PSU. Accordingly, in this paragraph we are talking about the number of SATA power plugs provided in the PSU. This number corresponds to the number of SATA drives that can be simultaneously powered from this model.
MOLEX
The number of Molex (IDE) connectors provided in the design of the power supply.
Initially, such a connector was intended to power peripherals for the IDE interface, primarily hard drives. And although the IDE itself is completely obsolete today and is not used in new components, however, the Molex power connector continues to be installed in power supplies, and almost without fail. Almost any modern PSU has at least
1 – 2 of these connectors, and in high-end models this number can be
7 or more. This situation is due to the fact that Molex IDE is a fairly universal standard, and with the help of the simplest adapters, components with a different power interface can be powered from it. For example, there are Molex - SATA adapters for drives, Molex - 6 pin for video cards, etc.
PCI-E 16pin
the 16-pin PCI-E power connector is designed to replace the existing 8-pin counterparts. It consists of twelve lines for current supply and four more for data transmission. The connector provides up to 600 W of additional power, which is a fourfold increase in power compared to 8-pin versions of the interface. Additional PCI-E connectors of all formats are used to power those types of internal peripherals that are no longer enough with 75 W supplied directly through the PCI-E socket on the motherboard.
Floppy
The presence of at least one Floppy power connector in the PSU.
Initially, this connector was intended to power floppy disk drives, hence the name. It is also known under the designation "mini-Molex". Anyway, this standard is generally considered obsolete, but it is still used by some specific types of components, and therefore continues to be used in power supplies.
+3.3V
The maximum values of current and power that the PSU can provide on individual power lines.
The power line can be simply described as a pair of contacts for connecting a particular load; one of these contacts is “ground” (with zero voltage), and the second has a certain voltage with a plus or minus sign, this voltage corresponds to the voltage of the power line. In this paragraph, it is + 3.3V (such power is present in 20- and 24-pin connectors for motherboards, in SATA power connectors and some other types of connectors).
In general, power and currents are rather specific parameters that the average user rarely needs — mainly when connecting high-power components such as video cards, as well as when starting a PSU without a computer to power other electronics (for example, amateur radio stations). It is also worth mentioning that the sum of the maximum powers on all lines can be higher than the total output power of the PSU — this means that all lines cannot operate at full power at the same time. Accordingly, when the PSU is fully loaded, some of them will produce less power than the maximum possible.
