▷ Types of screws for motherboards and pc in general

The screws of the PC case are the most used accessories to ensure the fixation of all the components to the case. Although there are numerous box manufacturers, they have generally used three thread sizes for their screws. In this articles we are going to see the different types of screws that are used in PC motherboards and cases.

Index of contents

Screws for PC: Types, materials, uses and examples

Below we see the types of screws most used in all PCs, as well as their characteristics, uses and some examples.

We recommend reading our article on Best motherboards on the market

UNC Screw # 6-32

UNC # 6-32 screws are often found on 3.5 ″ hard drives and the body of the case to secure the covers. M3 threaded holes are found in 5.25 "optical disk drives, 3.5" floppy drives, and 2.5 "drives. Motherboards and other circuit boards often use a showdown. UNC thumbscrews are often found at the ends of DVI, VGA, serial, and parallel connectors.

Screw # 6-32 UNC has a thread pitch of 0.7938 mm. UNC # 6-32 is a UTS screw that specifies a major thread diameter that is defined as 3.51 mm; and 32 threads per inch (tpi), which is equivalent to a thread pitch of 0.031250 0.7938 mm. The optional UNC specification indicates that the standard coarse thread is used, which is defined for # 6 screws as 32 tpi, making 'UNC' redundant, however it can be seen when other specifications such as coating u are also specified. other treatments. It is by far the most common screw found inside PC cases. It usually appears in lengths 4.76 mm and 6.4 mm, or less frequently 7.94 mm. Sometimes non-standard metric lengths are also found, such as 5 millimeters.

They are almost always fitted with a Phillips-type head, although a Torx unit is sometimes used instead. Phillips and Torx patterns can also be combined with a slot for a flat-blade screwdriver. They typically feature a 6.4mm flanged hex head. Flat head screws are also common: a low disk with a chamfered outer edge. Because they are used in places where high torque is not required and may need to be easily removed and replaced, they are often available as thumbscrews with larger knurled heads that can be removed by hand.

They are commonly used for the following purposes, however there are many exceptions:

• Securing a power supply to the box Securing a 3.5-inch hard drive to the box Holding an expansion card in place by its metal slot cover Holding the components of the box together

M3 screw

The M3 screw has a 0.5mm thread pitch, which is finer than the 0.7938mm pitch of a # 6-32 UNC screw. The M3 is a metric screw that specifies a nominal diameter of 3 millimeters, and a standard coarse thread pitch defined as 0.5 millimeters. The M3 is the second most common screw found on PCs. It usually appears in many lengths from 1 to 20 mm. Almost all new PC chassis come with a bag of these. M3 screws generally accept a Phillips n screwdriver bit. ° 2.

Despite many exceptions, they are commonly used to secure the following devices:

• 5.25-inch optical disc drives 2.5-inch hard drives and solid-state drive 3.5-inch floppy drives

Separators for motherboard

Most cases use threaded brass standoffs to attach the motherboard to the chassis of the case. Sometimes threaded or snap-lock plastic standoffs are used, which are less secure, but equally useful on a stationary PC. The spacer provides a margin of space between the motherboard and the box to keep multiple solder points below the ground connection and short circuit.

The spacer usually has a # 6-32 UNC male thread on one end that threads into a threaded hole in the motherboard case or back plate and a # 6-32 UNC female thread on the other end that accepts a screw to retain the motherboard. Less frequently, the spacer has a female thread on both ends and a second screw is used to secure it to the box. Some standoffs use M3 female thread in place of # 6-32 UNC, and on a rare occasion a mix of types can be used in the same case.

Version 2.1 of the ATX specification states that the length of the spacers must be at least 6.4mm, with their cross sections adjusted within 10mm x 10mm square areas, centered around each mounting hole in ATX Motherboards.

# 4-40 UNC hand screws

Pairs of # 4-40 UNC thumbscrews are used to secure certain connectors to the hardware ports. The screws are typically located on either side of the D-subminiature connectors, such as the ports on the legacy, serial, parallel, and VGA game controllers. They are also used more recently in DVI connectors. The typical length of a # 4-40 screw used in PC is 4.76mm.

Final words and conclusion about screws for motherboards and PC in general

We have to be clear that these are the most common screws in the main chassis manufacturers. But you can also find screws with a Torx head or with a special design. Many times they use these formats to interpose a barrier when opening your box or renovating some component.

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This ends our article on different types of screws for motherboards and PC in general, you can leave a comment if you have any questions or suggestions.

Wikipedia source