Short answer: only use the modular cables that came in the box with your power supply. Never reuse cables from an old unit, even from the same brand. It’s one of the few PC building mistakes that can destroy several parts in one go.
Why it’s dangerous
A modular cable has two ends. The end that plugs into your motherboard, graphics card or drives is standard. The end that plugs into the power supply is not. Each brand, and sometimes each generation from one brand, wires those sockets differently.
NZXT explains that a mismatched cable can send 12V where ground should be, creating a short that can destroy the power supply and the parts connected to it. Because the plug still fits, nothing warns you until you switch on.
Which end is standard?
| Cable end | Standard? | What it means |
|---|---|---|
| Device end: 24-pin, processor, graphics card, SATA | Yes | Fits and is wired the same on every power supply |
| Power supply end | No | Pin layout can differ between brands and between models |
| Graphics card 12V-2x6 or 12VHPWR end | Yes | The card end follows the standard. The power supply end still varies |
That’s why a cable can look perfect at the device end and still be wired wrong at the other.
It happens more than you'd think
In February 2026, Tom’s Hardware reported on a builder who destroyed a 14TB hard drive by plugging in a SATA power cable from a different power supply. The drive’s electronics were likely hit with 12V on a line meant for 5V.
It can catch out people who stay loyal to one brand too. NZXT says its newer Gold Core units can’t use cables from its own previous-generation C series.
When people get caught out
- Replacing a dead power supply and leaving the old cables routed behind the motherboard tray to save time.
- Grabbing a spare SATA cable from a drawer to add a new drive.
- Moving custom sleeved cables from an old build to a new power supply.
- Upgrading within a brand and assuming the cables carry over.
How to tell which cables you have
- Check the label on the power supply for the exact model number.
- Look for printing on the cables. Many makers print the cable type or series on the plug or a label near it.
- If a cable isn’t marked and you can’t be sure where it came from, don’t use it.
How to swap a power supply safely
- Switch off at the wall and unplug the mains cable.
- Remove every modular cable from the old unit, including ones hidden behind the motherboard tray.
- Bag the old cables with the old unit and label the bag.
- Fit the new unit and route only its own cables.
- Check each connection is fully seated before you switch on, especially the graphics card plug. See the ATX 3.1 guide.
Custom cables
Sleeved custom cables are fine, as long as they’re made for your exact power supply model. Check the maker’s compatibility list against the model number on your unit’s label, not just the brand. When you change power supply, you’ll usually need a new set.
If you’ve already used the wrong cable
- Switch off and unplug straight away. Don’t power on again to check.
- Swap in the correct cables, then test the parts that were connected to the wrong one, one at a time if you can.
- Contact the makers of any damaged part. NZXT says damage from incompatible cables isn’t covered by its warranty, so be honest about what happened.
Replacing a power supply?
Every pick below comes with a full set of its own cables. Size it first with the wattage guide.
- Safe all-rounder · Tier ACorsair RMx (2024)80 Plus Gold · Fully modular · ATX · 750/850/1000WFully modular, quiet at everyday loads, with fan failure protection.Check 850W price
- Compact · Tier ASeasonic Core GX ATX 380 Plus Gold · Fully modular · ATX · 650/750/850WFully modular and only 140mm deep.Check 850W price
Questions
Are Corsair cables compatible between models?
Don’t assume so. Even within one brand, cable types change between generations. Use the cables supplied with your unit.
Does the warranty cover damage from the wrong cable?
NZXT says damage from incompatible cables isn’t covered by its warranty, and other brands are likely to take the same view.
Can I reuse cables if I’m replacing a unit with the exact same model?
Only if you’re certain it’s the same model and revision. If there’s any doubt, use the new cables.
Is it safe to use a SATA cable from another power supply just for a fan?
No. The wiring at the power supply end can be different, and a short can damage more than the fan.
What about non modular power supplies?
The cables are fixed to the unit, so the problem can’t happen. It only applies to cables that unplug at the power supply end.
Sources
- NZXT: PSU cable compatibility
- Tom's Hardware: enthusiast fries 14TB drive with the wrong SATA cable (February 2026)
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