Question What would happen to a high wattage PSU if you didn't use the official/supplied cable ?

Gamefreaknet

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Mar 29, 2022
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Now I know this sounds (maybe) stupid/unreasonable to do however lets say by some chance you have a 1000w PSU and you lose its original cable. You look around and see another PC PSU cable from maybe an old desktop that died/is no longer used or whatever.
Generally high wattage PSU cables are THICK (I know myself from having a Corsair 1000w PSU). However, lets say I found another cable that fitted the connector for the 1000w PSU, and was (since I'm from the UK) 250v 13A rated would that cable be able to supply the same 1000w just like the original cable that came with the PSU or would there be cable stress, not enough power delivery (due to a thinner cable) or something else?

(Do note I do not intend to do this... just curious what would happen)
 
Not all PSU's will have the same pinout for their PSU's, so if you do use aftermarket cables that aren't meant for your PSU, you can ruin the PSU or the components or both. Just because you can poke a fork in a live socket in your wall outlet, doesn't mean you should do it.
 
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Also if you're talking about the mains cable, the part that connects to the PSU is standardized and the shape of said connector determines how many amps can be carried through it. See https://en.wikipedia.org/wiki/IEC_60320#Appliance_couplers

Typically connector C13/C14 is used, which can handle 10A. Since the UK runs off 230V, that means it can handle 2300W. Sometimes C19/C20 is used for higher wattage PSUs, which can handle another 6A.

Though it's very unlikely your PC will actually hit 1000W unless you're running an RTX 4090 and an i9-13900K.
 
That got me thinking.

If a standard UK mains plug to IEC 60320 C13 power cord is rated a 10A, why do most suppliers fit a 13A fuse and not a 10A fuse in the plug top. British mains plug fuses come in 2A, 3A, 5A, 7A, 10A and 13A ratings. For a table lamp I'd fit a 2A or 3A fuse.

If you look at the time vs current curve for a standard 13A Fast/medium speed British plug top fuse, it requires a continuous (steady state) current of 20A for at least 700 seconds, before the fuse will "blow". Higher fault currents will cause the 13A fuse to fail much faster, e.g. 1,000A in 1 millisecond. See page 3 in document link below.
https://docs.rs-online.com/9819/0900766b8002b71e.pdf

Regardless of the "correctness" of fitting a 13A fuse in the plug, the implication is that any well manufactured IEC lead should be capable of supplying a 1kW ATX PSU with ease.
 
If a standard UK mains plug to IEC 60320 C13 power cord is rated a 10A, why do most suppliers fit a 13A fuse and not a 10A fuse in the plug top. British mains plug fuses come in 2A, 3A, 5A, 7A, 10A and 13A ratings. For a table lamp I'd fit a 2A or 3A fuse.
The 10A rating is what the IEC specifies. In the section before the one in the link I posted, apparently North American standards can certify C13/C14 up to 15A.

So if the UK has the equivalent of UL (which is a certification company in the US), then they may be doing the same thing.

Also the maximum value of most connector standards are underrated against their actual maximum (whatever that is) anyway for headroom and/or safety margins.
 
DO NOT MIX CABLES!!! Unless you like things shorting and burning and smoking.

If you are missing cables and need them, cable mod is probably the cheapest solution, Corsair thinks their cables are worth gold.

Thinker wire is always going to be better, but not always worth it, Most decent PSU wires range from 18 to 16 gauge, seen some rare units that used 14. Some vary cheap units that used 26 gauge. As long as its 18 or 16 gauge, you really do not need anything thicker for PC components, its such a short run anyway and 12v, the resistant's wouldn't matter.

I would be more worried about the power cable that goes from your wall to the PSU, if its a 18 gauge at 110v can handle up to 600 watts, It could handle more, but it would be unstable, potentially causing issues, and the cord to warm up if much more than that, a potential fire hazard, most OEM's still use 18 gauge, but their PC's don't use much power so. If its 16 gauge, which can handle up to 1400 watts, 14 gauge 1800 watts, and can have the potential to help with lower resistance better overclocks, but not really an issue with 98% of users.
 
Everyone that says "dont mix cables, use a 100$ cord from a modding company", how it was said, it is a standard, you can just go buy a cable that supports the Amps which your PSU draw and you are fine. Look on the PSU at 240VAC how many amps needs and search for the equivalent standard cable.
 
Interesting to hear of differences in the current rating of the same cable in different parts of the world.

As a rule of thumb at work, we de-rated all mains cables to 50%, to cope with self-heating effects of bundled wires in trunking and hot climates.

In Europe the equivalent of Underwriters Laboratory is CE.

When checking systems for EMI and EMC compliance in anechoic chambers, I tested for both sides of the Atlantic, i.e. UL and CE.
 
DO NOT MIX CABLES!!! Unless you like things shorting and burning and smoking.

If you are missing cables and need them, cable mod is probably the cheapest solution, Corsair thinks their cables are worth gold.

Thinker wire is always going to be better, but not always worth it, Most decent PSU wires range from 18 to 16 gauge, seen some rare units that used 14. Some vary cheap units that used 26 gauge. As long as its 18 or 16 gauge, you really do not need anything thicker for PC components, its such a short run anyway and 12v, the resistant's wouldn't matter.

I would be more worried about the power cable that goes from your wall to the PSU, if its a 18 gauge at 110v can handle up to 600 watts, It could handle more, but it would be unstable, potentially causing issues, and the cord to warm up if much more than that, a potential fire hazard, most OEM's still use 18 gauge, but their PC's don't use much power so. If its 16 gauge, which can handle up to 1400 watts, 14 gauge 1800 watts, and can have the potential to help with lower resistance better overclocks, but not really an issue with 98% of users.
Where are you getting your ratings from?
 
Everyone that says "dont mix cables, use a 100$ cord from a modding company", how it was said, it is a standard, you can just go buy a cable that supports the Amps which your PSU draw and you are fine. Look on the PSU at 240VAC how many amps needs and search for the equivalent standard cable.
Yeah go right a head and try it, have a camera ready just in case it pops your GPU or board and everything you own in that rig, It'll work
 
Everyone that says "dont mix cables, use a 100$ cord from a modding company", how it was said, it is a standard, you can just go buy a cable that supports the Amps which your PSU draw and you are fine. Look on the PSU at 240VAC how many amps needs and search for the equivalent standard cable.
No. Its not the amps or watts, it is the actual connection.

At the GPU end, the pinout is the same.

At the PSU end, it is NOT standardized.

Use the wrong cable, and you may well smoke either or both parts.