Halfway through a first build, it’s a common moment of panic: the motherboard is out of its static bag, but where are the screws supposed to hold it in place? Do PC cases come with motherboard screws, or is that something that should have shipped with the motherboard itself?
- Motherboard mounting screws and standoffs almost always ship with the case, not the motherboard.
- Most cases include a small parts bag with standoffs, case screws, and sometimes zip ties.
- Standard standoffs use 6-32 UNC threading in most consumer cases, matching standard motherboard screws.
- Losing the bag is common, and replacement screws are cheap and widely available at hardware stores.
Where the Screws Actually Come From
It is a common assumption that the motherboard box should include its own mounting hardware, but that is backwards. The case is what provides the standoffs (the small brass or steel pegs the motherboard sits on) and the screws that go into them.
A typical case accessory bag includes:
- Motherboard standoffs (sometimes preinstalled, sometimes loose)
- Motherboard mounting screws
- Drive bay screws for SSDs and hard drives
- Fan screws
- Zip ties for cable management
- An I/O shield, if not already built into the motherboard
According to Wikipedia’s rundown of computer case screw standards, the most common thread type for case and motherboard screws in ATX-style builds is 6-32 UNC, though some smaller form factor cases use M3 hardware instead.
Preinstalled Standoffs vs Loose Standoffs
Cases handle this two different ways, and it is worth knowing which type is in hand before starting a build.
- Preinstalled standoffs: Many modern cases already have brass standoffs screwed into the motherboard tray at standard ATX positions. Builders just line up the board and drive in the top screws.
- Loose standoffs: Some cases, especially ones supporting multiple motherboard sizes (ATX, mATX, ITX), leave standoffs loose so the builder can place them in the correct holes for their specific board size.
Either way, the case is doing the heavy lifting on hardware, not the motherboard box.
Tip: Before mounting a board, lay it inside the case (unscrewed) and check that every standoff lines up with a screw hole. A single misplaced standoff touching the back of the motherboard can short the board when it powers on.
What If the Screw Bag Is Missing or Lost
It happens more often than people expect, especially with used cases or ones bought without original packaging.
- Local hardware or computer stores often carry generic 6-32 motherboard screws.
- Online retailers sell assorted PC building screw kits for a few dollars.
- Some case manufacturers will mail a replacement accessory bag if contacted directly with a case model and order number.
Motherboard Box Hardware: What It Actually Includes Instead
Motherboard boxes are not empty of hardware, they just include different things. Typical motherboard accessory kits have SATA cables, a driver disc or QR code, sometimes Wi-Fi antennas, and an I/O shield if it is not preattached. Mounting screws are simply not part of that kit because the case vendor already supplies them.
1. Do all motherboards need the same size screws?
Most ATX, mATX, and Mini-ITX boards use the same 6-32 UNC screw and standoff standard, which is why cases can include a single universal hardware bag. A few specialty boards or SFF cases use M3 hardware instead, so it is worth checking the case manual if unsure.
2. What happens if I use the wrong screws for my motherboard?
Forcing the wrong thread size can strip the standoff or the motherboard hole, or leave the board sitting unevenly. If a screw does not turn smoothly by hand, it is the wrong size, not a screw that needs force.
3. Can I build a PC without standoffs?
No, not safely. Standoffs keep the motherboard’s underside from touching the metal case, which prevents short circuits. Skipping them risks damaging the board the moment it is powered on.
4. Do prebuilt PCs include extra screws for upgrades later?
Sometimes, but not always. Many prebuilt systems ship with just enough hardware for the components installed at the factory, so adding a drive or fan later may require picking up extra screws separately.
The Bottom Line
The case is the source of motherboard screws and standoffs, not the motherboard box. Checking the case’s accessory bag before assuming hardware is missing saves a lot of unnecessary worry during a first build.
This article reflects general PC building guidance based on publicly available manufacturer information at the time of writing; always check the included manual for the exact hardware that ships with a specific case model.
