Comparison Chieftec VEGA M PPG-850-C vs Deepcool PN-D PN850D

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").

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.

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.

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.

Number of 8-pin PCIe power connectors (6+2) provided in the PSU design.

Additional PCIe power connectors (of all formats) are used for additional power to types of internal peripherals that require more than the 75W supplied directly through the PCIe slot on the motherboard (a typical example is graphics cards). In PC components, there are two types of such connectors — 6-pin, providing up to 75W of additional power, and 8-pin, giving up to 150W. The 8-pin (6+2) connectors used in power supplies are universal: they can work with both 6-pin and 8-pin connectors on the expansion board. Therefore, this type of connector is the most popular in modern PSUs.

As for the quantity, there are models on sale with 1 PCIe 8-pin (6+2) connector, 2 such connectors, 3 connectors, 4 connectors, and in some cases — 6 or more. Several of these connectors can be useful, for example, when connecting multiple graphics cards — or for a powerful high-performance video adapter equipped with multiple additional PCIe power connectors.

The cable system used in the power supply. According to this parameter, modular, semi- modular and non-modular devices are distinguished, here are their features:

— Not modular. The classic version of the design, used in computer power supplies from the very beginning and not losing popularity to this day. The wires in such systems have a non-detachable design, and additional cables are not provided for connection. As a result, the user has to deal with only those cables that the manufacturer provided, without the ability to remove or replace them (the only modifications available are the installation of additional accessories such as an extension cord or splitter). Because of this, such PSUs are less convenient than modular and semi-modular ones: their wires are often excessively long, and some of them are not used at all, while such an “economy” further clutters up the case, worsening air circulation and cooling efficiency. On the other hand, these shortcomings can be reduced to almost zero with careful selection of the PSU and careful wiring; and non-modular systems themselves are distinguished by reliability and at the same time low cost. It is because of these features that they are most common nowadays.

— Modular. Systems in which each cable is made detachable; special sockets are used for fastening wires. Thanks to this design, you can optimally organize the space inside the PC —...for example, remove unnecessary wires so that they do not interfere with air circulation in the system unit; replace a cable that is too long with a shorter wire (or vice versa); swap cables, etc. At the same time, modular systems are noticeably more expensive than non-modular ones, while they are considered somewhat less reliable due to the presence of "weak points" in the form of removable cable mounts.

— Semi-modular. A kind of compromise between the options described above: some of the wires in such power supplies are made non-removable, some are equipped with modular mounts. This makes it possible to partially combine the advantages and compensate for the disadvantages of the two systems: semi-modular PSUs are less expensive and more reliable than modular ones, and at the same time more convenient than non-modular ones. Usually, in systems of this type, the most important wires have a non-removable design, which are almost guaranteed to be used when assembling a PC, and secondary cables are equipped with removable mounts and can be removed if not needed. However, the specific features of a semi-modular PSU should be specified separately.

The maximum current the PSU can deliver on the first +12V power line.

For more information on power lines in general, see the "+3.3V" section. Here, it is worth mentioning that 12V is the most popular voltage among computer power connectors. It is used in almost all such connectors (with few exceptions), and some plugs (for example, additional PCI-E power with 6 or 8 connectors) use only 12-volt lines — specifically in the +12V format. The division of +12V power into several separate lines is done for safety reasons — to reduce the current going 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 provide only the overall value in the specifications; in such cases, this number is indicated in this section.

The maximum power that the PSU can deliver to the +12V power rail.

For more details on power rails in general, see "Maximum current and power." Here, it should be noted that 12V is the most popular voltage among computer power connectors. It is used in nearly all such connectors (with few exceptions), and some plugs (such as the additional PCI-E power for 6 or 8 connectors) use only 12-volt rails, specifically in the +12V format. Therefore, this indicator is one of the most important characteristics of any PSU.

It is worth noting that many PSUs have multiple separate +12V power rails. In such cases, the total power is indicated here, which is usually divided equally among the rails.

The maximum power that the PSU is capable of delivering on the + 3.3V and + 5V power lines.

See "Maximum current and power" for details on power lines in general. Here we note that the power lines + 3.3V and + 5V are used both in the general connector for the motherboard (for 20 or 24 pins), and in specialized plugs — in particular, the SATA power connector (both) and Molex (only +5V, in addition to +12V). The power of these lines is a rather specific parameter, rarely required in fact; it is usually the same for both voltages, so it is indicated in the general clause.