GUIDE
Modular vs semi-modular vs non-modular power supplies
Modular just means the cables unplug from the power supply. It makes building and cable management easier but doesn't change how well the PSU powers your PC. The one rule: never mix modular cables between power supplies.
The three types
| Type | What unplugs | Good for |
|---|---|---|
| Non-modular | Nothing. Every cable is fixed. | Budget builds, cases with room to hide spare cables |
| Semi-modular | PCIe, SATA and accessory cables. The 24-pin, and usually the CPU cable, stay fixed. | Most builds |
| Fully modular | Every cable | Small cases, custom sleeved cables, swapping parts often |
Does modular change performance?
Not in any way you'd notice. The extra connector at the PSU end adds a tiny bit of resistance, but a decent unit's voltages are the same either way. Efficiency, noise and reliability come from the power supply's design, not its cable style.
The rule that matters: never mix modular cables
The plugs at the parts end of a modular cable are standard. The plugs at the PSU end are not. Different brands, and even different models from the same brand, can put 12V, 5V and ground on different pins.
Plug in a cable from another power supply and you can send 12V down a wire your drive or graphics card expects to be ground. That can kill hardware the moment you power on, and it's a common way people fry parts during a PSU swap.
- Replacing a modular PSU? Pull every old cable out of the case, even the ones that look identical.
- Keep spares labelled. Store each power supply's extra cables in their own bag with the model name on it.
- Buying custom sleeved cables? Buy them for your exact PSU model or series, and check the cable maker's compatibility list.
Which one should you buy?
Semi-modular is the best value for most builds: the cables you always use stay attached, and the ones you might not need come off. Go fully modular for a small case or if you change parts often. Non-modular is fine for a budget build if the case has room behind the motherboard tray to tuck the spare cables away.
Cable count matters more than cable style
Whatever type you pick, check it has enough separate PCIe cables for your graphics card, or a native 16-pin cable if your card uses one. How to check what connectors your PSU has shows what to look for.
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