Comparison MSI MAG GN PCIE5 A750GN vs Deepcool PN-D PN750D

The bearing is the piece between the rotating axle of the fan and the fixed base that supports the axle and reduces friction. The following types of bearings are found in modern fans:

— Sliding. The action of these bearings is based on direct contact between two solid surfaces, carefully polished to reduce friction. Such devices are simple, reliable and durable, but their efficiency is quite low — rolling, and even more so the hydrodynamic and magnetic principle of operation, provide much less friction.

— Rolling. They are also called "ball bearings", since the "mediators" between the axis of rotation and the fixed base are balls (less often — cylindrical rollers) fixed in a special ring. When the axis rotates, such balls roll between it and the base, due to which the friction force is very low — noticeably lower than in plain bearings. On the other hand, the design turns out to be more expensive and complex, and in terms of reliability it is somewhat inferior to both the same plain bearings and more advanced hydrodynamic devices. Therefore, although rolling bearings are quite widespread nowadays, however, in general, they are much less common than the mentioned varieties.

— Hydrodynamic. Bearings of this type are filled with a special liquid; when rotated, it creates a layer on which the moving part of the bearing slides. In this way, direct contact between hard surfaces is avoided and friction is significantly reduced compared to previous...types. Also, these bearings are quiet and very reliable. Of their shortcomings, a relatively high cost can be noted, but in fact this moment often turns out to be invisible against the background of the price of the entire system. Therefore, this option is extremely popular nowadays, it can be found in cooling systems of all levels — from low-cost to advanced.

— Magnetic centering. Bearings based on the principle of magnetic levitation: the rotating axis is "suspended" in a magnetic field. Thus, it is possible (as in hydrodynamic ones) to avoid contact between solid surfaces and further reduce friction. Considered the most advanced type of bearings, they are reliable and quiet, but expensive.

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 PCI-E 8pin (6+2) power connectors provided in the PSU design.

Additional PCI-E power connectors (all formats) are used to additionally power those types of internal peripherals for which 75 W is no longer enough, supplied directly through the PCI-E socket on the motherboard (video cards are a typical example). In PC components, there are two types of such connectors — 6pin, providing up to 75 W of additional power, and 8pin, giving up to 150 W. And the 8pin (6 + 2) plugs 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 plug is the most popular in modern PSUs.

As for the quantity, on the market you can find models for 1 PCI-E 8pin (6 + 2) connector, for 2 such connectors, for 4 connectors, and in some cases — for 6 or more. Several of these plugs can be useful, for example, when connecting several video cards — or for a powerful high-performance video adapter equipped with several PCI-E additional power connectors.

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.

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.

Protection circuits provided in the power supply. In addition to the OVP (overvoltage protection), OPP (overcurrent/power protection), and SCP (short circuit protection) described above, modern PSUs may include the following safety features:

— O.C.P. Overload protection on individual power outputs. It differs from OPP in that it takes into account not the total current consumption, but the current at each output separately.

— UVP. Undervoltage protection at the output of the power supply. For some components, such a voltage is as undesirable as an increased voltage: for example, a hard drive at reduced power cannot spin the plates to the required speeds. Usually, UVP is activated when the voltage drops by 20 – 25%.

— OTP. Protection against overheating of individual components of the power supply.

— SIP. Protection against voltage surges and surges is, in fact, a built-in stabilizer that can smooth out these surges to a certain extent. This feature does not eliminate the need for an external stabilizer, but it improves the overall performance of the protection.

— A.F.C. Not so much a protective as an “energy saving” function: automatic fan speed control, which allows you to change the speed depending on the load and the actual heat dissipation of the PSU. In addition to saving energy, this adjustment also reduces wear on the moving parts of the cooler.

— C.E. Power supply complies with European Union dire...ctives for energy efficiency and safety.

— CB. Power supply complies with IEC (International Electrotechnical Commission) directives regarding the safety of electrical equipment and components.

— FCC. Power supply complies with FCC (Federal Communications Commission) directives, especially regarding electromagnetic interference.

— CCC. Compliance of the power supply with the requirements necessary for official certification in the Chinese market (PRC).

— K.C. Compliance of the power supply with the requirements necessary for official certification in the South Korean market.

— BSMI. Compliance of the power supply with the requirements required for official certification in the Taiwan market.

— RCM. Power supply meets the requirements for official certification in the Australian and New Zealand market. RCM requirements are primarily concerned with safe use and electromagnetic compatibility.

— TUV-RH. Power supply meets the criteria for certification by TÜV Rheinland Group, one of the world's largest and most respected auditing and certification companies. Most often, we are talking about the TÜV-Mark Approval certificate, which indicates that the individual parts of the device (body, boards, parts, switches, etc.) comply with the requirements for safe use.

— cTUVus. Another certification held by the above mentioned TÜV Rheinland Group. In this case, we are talking about the compliance of the power supply with the technical requirements necessary for admission to the markets of the USA and Canada. The cTUVus certificate has the same legal validity as certificates issued directly by the authorities in those countries.

— EAC. Compliance of the power supply with the technical requirements of the Eurasian Economic Union (former Customs Union).

Manufacturer's warranty provided for this model.

In fact, this is the minimum service life promised by the manufacturer, subject to the rules of operation. There are both models with a small warranty up to 3 years, and more advanced power supplies, in which the warranty can reach 7, 10 years and even 12 years. In general , a 5-year warranty(for example) does not mean that the device will fail after the specified time. Most often, the actual service life of the device is much longer than the guaranteed one.

Specific warranty periods may vary even for similar drives from the same manufacturer. So not