Comparison ASRock B450 Pro4 vs ASRock B450M Pro4

The form factor of the motherboard determines, first of all, its physical dimensions, and, accordingly, a number of parameters directly related to them: type of computer case, installation method, type of power connector, number of slots for additional boards (expansion slots), etc. At the moment, there are such main form factors of motherboards:

— ATX. One of the most common form factors for PC motherboards. The standard size of such a board is 30.5x24.4 cm, it has up to 7 expansion slots and a 24-pin or (less often, in older models) 20-pin power connector.

— Micro-ATX. A slightly reduced version of the ATX form factor, with more compact dimensions (usually 24.4x24.4 cm) and, accordingly, fewer places for peripherals — there are usually only two slots for "RAM", expansion slots — from two to four. Nevertheless, despite the limited size, such boards can be intended for quite powerful systems.

— Mini-ITX. Motherboards of compact dimensions (17x17 cm). Designed for use primarily in small form factor computers (small form factor, SFF), in other words, compact PCs. According to the mounting specifications and the location of connectors and slots, they are compatible with ATX standard cases. They usually have one expansion slot.

— mini-STX. Another representative of compact form factors, assuming a boar...d size of 140x147 mm. Thus, the overall size is almost a third smaller than mini-ITX. At the same time, such motherboards often have seats for fairly powerful processors (for example, the LGA 1151 socket for Intel Core chips) and are made based on the corresponding TDP values. But expansion slots, usually, are absent.

— micro DTX. A relatively new compact form factor, which is not common, mainly among rather specific motherboards — in particular, models designed for cases in the PIO form factor. This form factor is characterized by a very small size and weight and allows you to mount the case directly behind the monitor, on a standard VESA mount. One of the features of "motherboards" for such systems is that the graphics card is installed along the board, and not perpendicularly — accordingly, the PCIe 16x connector (see below) has a non-standard location. At the same time, micro-DTX boards are similar in terms of fasteners to microATX and can be used in cases of the corresponding form factor (except that additional equipment may be required for the correct installation of a graphics card). The standard size of such a board is 170 x 170 mm, similar to mini-ITX.

— mini DTX. An intermediate format between the microDTX described above and the original DTX; sometimes also described as an extended mini-ITX version. It has a standard size of 170 x 203 mm and can be equipped with two expansion slots (mini-ITX and mini-DTX have one such slot); it is completely similar in application — it is intended mainly for compact cases, in particular, HTPC computers.

— XL-ATX. Larger version of the ATX form factor. While not yet a common standard, size options include 32.5x24.4cm with 8 expansion slots and 34.3x26.2cm with up to 9 expansion slots.

— Thin mini-ITX. A “thin” version of the reduced mini-ITX form factor described above: according to the official specification, the total thickness of the thin mini-ITX board should not exceed 25 mm. Also designed for the most miniature computers — in particular, HTPC.

— E-ATX. The letter E in the name of this form factor stands for "Extended" — extended. True to its name, E-ATX is another enlarged version of ATX using 30.5x33cm boards.

— EEB. Full name SSI EEB. The form factor used in server systems (see “By direction”) provides a board size of 30.5x33 cm.

— CEB. The full name is SSI CEB. Another form factor of "server" motherboards. In fact, it is a narrower version of the EEB described above, with a width reduced to 25.9 cm (with the same height of 30.5 cm).

— flex-ATX. One of the compact variations of ATX, which provides board dimensions of less than 229x191 mm, as well as less than 3 expansion slots. At the same time, in terms of the location of the mounting holes, this standard is identical to microATX; in fact, it was developed as a potential replacement for the latter, but for a number of reasons it did not receive much distribution, although it continues to be produced.

— Non-standard (Custom). The name Proprietary is also used. Motherboards that do not conform to standard form factors and are designed for cases of special sizes (usually branded ones).

Motherboard dimensions in height and width. It is assumed that the traditional placement of motherboards is vertical, so in this case one of the dimensions is called not the length, but the height.

Motherboard sizes are largely determined by their form factors (see above), however, the size of a particular motherboard may differ slightly from the standard adopted for this form factor. In addition, it is usually easier to clarify the dimensions according to the characteristics of a particular motherboard than to look for or remember general information on the form factor. Therefore, size data can be given even for models that fully comply with the standard.

The third dimension — thickness — is considered less important for a number of reasons, so it is often omitted.

The ability of the motherboard to work with RAM modules that support XMP (Extreme Memory Profiles) technology. This technology was developed by Intel; it is used in motherboards and RAM blocks and only works if both of these system components are XMP compliant. A similar technology from AMD is called AMP.

The main function of XMP is to facilitate system overclocking (“overclocking”): special overclocking profiles are “sewn” into the memory with this technology, and if desired, the user can only select one of these profiles without resorting to complex configuration procedures. This is not only easier, but also safer: every profile added to the bar is tested for stability.

Number of SATA 3 ports on the motherboard.

SATA is now the standard interface for connecting internal drives (mainly HDDs) and optical drives. One device is connected to one such connector, so the number of SATA ports corresponds to the number of internal drives / drives that can be connected to the motherboard through such an interface. A large number ( 6 SATA ports and more) is necessary in case of active use of several hard drives and other peripherals. For domestic use, 4 is enough. SATA 3, as the name suggests, is the third version of this interface, operating at a total speed of about 6 Gbps; the useful speed, taking into account the redundancy of the transmitted data, is about 4.8 Mbps (600 MB / s) — that is, twice as much as in SATA 2.

Note that different SATA standards are quite compatible with each other in both directions: older drives can be connected to newer ports, and vice versa. The only thing is that the data transfer rate will be limited by the capabilities of the slower version, and in some cases it may be necessary to reconfigure the drives with hardware (switches, jumpers) or software. It is also worth saying that SATA 3 is the newest and most advanced variation of SATA today, but the capabilities of this standard are not enough to unlock the full potential of high-speed SSDs. Therefore, SATA 3 is mainly used for hard drives and low-cost SSDs, faster drives are conn...ected to specially designed connectors like M.2 or U.2 (see below).

Electrical (logical) interfaces implemented through physical M.2 connectors on the motherboard.

For more details about such connectors, see above. Here, we note that they can work with two types of interfaces:

• SATA — a standard originally created for hard drives. Usually, the most recent version supported in M.2 is SATA 3; however, even it is significantly inferior to PCIe in terms of speed (600 MB/s) and functionality (only storage devices);
• PCIe — the most widespread modern interface for connecting internal peripherals (also known as NVMe). It is suitable for various expansion cards (such as wireless adapters) as well as storage devices, with PCIe speeds allowing for the full potential of modern SSDs to be realized. The maximum data transfer speed depends on the version of this interface and the number of lanes. In modern M.2 connectors, you can find PCIe versions 3.0 and 4.0, with speeds of approximately 1 GB/s and 2 GB/s per lane, respectively; and the number of lanes can be 1, 2, or 4 (PCIe 1x, 2x, and 4x, respectively)

Specifically, the M.2 interface in motherboard specifications is indicated by the number of connectors themselves and the type of interfaces provided in each of them. For example, the entry "3xSATA/PCIe 4x" means three connectors capable of operating in both SATA and PCIe 4x formats; and the designation "1xSATA/PCIe 4x, 1xPCIe 2x" means two connectors, one of which works as SATA or PCI...e 4x, and the other only as PCIe 2x.

The number of PCIe (PCI Express) 1x slots installed on the motherboard. There are motherboards with 1 PCIe 1x slot, 2 PCIe 1x connectors, 3 PCIe 1x ports, and even more.

The PCI Express bus is used to connect various expansion cards—network and sound cards, video adapters, TV tuners, and even SSDs. The number in the name indicates the number of PCIe lanes (data transmission channels) supported by this slot; the more lanes, the higher the bandwidth. Accordingly, PCIe 1x is the basic, slowest variety of this interface. The data transfer rate for such slots depends on the PCIe version (see "PCI Express Support"): specifically, it's just under 1 GB/s for version 3.0 and just under 2 GB/s for version 4.0.

It is worth noting that the general rule for PCIe is this: the card should be connected to a slot with the same or greater number of lanes. Thus, only single-lane cards will be guaranteed to be compatible with PCIe 1x.

The motherboard has its own DVI output; this clause also specifies the specific form of this interface.

Such an output is intended for transmitting video from an integrated graphics card (see above) or a processor with integrated graphics (we emphasize that it is impossible to output a signal from a discrete graphics card through the motherboard chipset). As for DVI specifically, this is a standard originally created for digital video devices, however, it also allows an analogue signal format, depending on the type. In modern computer technology, including motherboards, you can find two types of DVI:

— DVI-D. A standard that provides for the transmission of a signal only in digital form. Depending on the supported mode, the maximum resolution of such video can be 1920x1200 (single-link Single Link) or 2560x1600 (two-channel Dual Link); however, Single Link plugs can be connected to Dual Link ports, but not vice versa. Also note that such connectors are compatible with HDMI via adapters, while in some cases even sound transmission may be provided (although this function is not initially supported in DVI-D, and its availability should be specified separately).

— DVI-I. A standard that combines the DVI-D described above with analogue DVI-A and allows the signal to be output in both digital and analogue formats. DVI-A in its characteristics corresponds to VGA (see above): it supports resolutions up to 1280x1024...inclusive and allows you to connect VGA screens through a simple adapter.