Power Supply Appropiate wire gauge (AWG) for ATX cables?

Arc_Lag

Caliper Novice
Original poster
Jul 2, 2019
32
5
Hi guys! I've been wanting to create a custom solution for my build soon but I was wondering whether or not it will be alright to pair lets 20 AWG with a SF750.
Will that turn out fine? Or should I consider going a step thicker with 18 AWG.

What do you guys reckon?
 

T4iga

Chassis Packer
Jun 21, 2019
20
6
For anything that sips power you should use 18 or thicker i think. Manufactures use that far the most part as far as i know. If i were to make my own camles again i wouldn't save an copper. It is expensive and time consuming overall and geing for 16AWG doesn't beork the bank if custom wiring doesn't yet do it!
I have worked with MD-PCX stuff and can highly recommend it btw
 
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Arc_Lag

Caliper Novice
Original poster
Jul 2, 2019
32
5
For anything that sips power you should use 18 or thicker i think. Manufactures use that far the most part as far as i know. If i were to make my own camles again i wouldn't save an copper. It is expensive and time consuming overall and geing for 16AWG doesn't beork the bank if custom wiring doesn't yet do it!
I have worked with MD-PCX stuff and can highly recommend it btw
Thank you for the valuable information! I'll steer clear from anything thinner than 18 AWG!
 

Tuscany

SFF Lingo Aficionado
Apr 26, 2020
92
36
I went with the 15AWG from MDPC - for 6/8/24 pins and 17AWG for Sata/Molex. Keep in mind that the 15AWG are quite hard to work with - crimping, sleeving, inserting, routing.
But they look awesome with the MDPC sleeving :)
 
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EndingCredits

Caliper Novice
Dec 17, 2020
21
5
Just a quick note that might be worth considering:

Resistance in a wire is proportional to length divided by the square of the diameter. Resistance is ultimately what causes power loss due to transmission (with power loss in proportion to resistance for a given current). Hence for shorter cable runs, such as those in SFF systems, you could, IN THEORY****, get away with thinner cables than in a typical full sized ATX system.

**** There's lots of other factors here, such as shorter wires dissipating less heat, and I'm not an expert on this, so take that with a grain of salt. TBH I'd want to hear from someone who actually knows what they're talking about before I went above 18AWG.
 
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Arc_Lag

Caliper Novice
Original poster
Jul 2, 2019
32
5
I went with the 15AWG from MDPC - for 6/8/24 pins and 17AWG for Sata/Molex. Keep in mind that the 15AWG are quite hard to work with - crimping, sleeving, inserting, routing.
But they look awesome with the MDPC sleeving :)
Haha nice! I'm actually trying to go for thinner cables instead of thicker. I've had some issues with stock atx cables in the past being a b**** to work with in sff cases. Hence the question for how thin I can go :p
 

facepalmjohannes

Minimal Tinkerer
New User
Dec 24, 2020
4
10
I went with the 15AWG from MDPC - for 6/8/24 pins and 17AWG for Sata/Molex. Keep in mind that the 15AWG are quite hard to work with - crimping, sleeving, inserting, routing.
But they look awesome with the MDPC sleeving :)
Everybody please keep this in mind. Its a pain in the ass to sleeve 15AWG wires! Do not do this unless you really like burning pain in your fingertips. Even cable combs won't fit properly, at least not the ones I tried from MDPC-X. I broke almost all of them, worst day of my life. But hey - at least it looks good. Just use 17AWG.
 

T4iga

Chassis Packer
Jun 21, 2019
20
6
Everybody please keep this in mind. Its a pain in the ass to sleeve 15AWG wires! Do not do this unless you really like burning pain in your fingertips. Even cable combs won't fit properly, at least not the ones I tried from MDPC-X. I broke almost all of them, worst day of my life. But hey - at least it looks good. Just use 17AWG.
According to MDPC their 15AWD is in thinner insulation os it should have the same thickness as regular 16AWG which worked perfectly for me. I went with metal cable combs in by Alphacool. I think they are called Eiskamm and they are very sturdy and look phenomenal. If you manage to break those using only cables chances are you'll probably break a lot more expensive parts while building lol
 
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facepalmjohannes

Minimal Tinkerer
New User
Dec 24, 2020
4
10
According to MDPC their 15AWD is in thinner insulation os it should have the same thickness as regular 16AWG which worked perfectly for me. I went with metal cable combs in by Alphacool. I think they are called Eiskamm and they are very sturdy and look phenomenal. If you manage to break those using only cables chances are you'll probably break a lot more expensive parts while building lol
Haha that might be true. I just went with acrylic one though, should give metal a chance.

According the gauge - it was ecspecially hard to fit them in the connector. Guess that is due to the slightly bigger pins wich you crimp around.
 

Arc_Lag

Caliper Novice
Original poster
Jul 2, 2019
32
5
Hey, I've been thinking this whole time and then I saw PSlate, I'm certain that their cables don't use 17 AWG or 18 at that matter, looks more like 23. Can you confirm?


Or am I simply making a mistake and those cables are 17/18 AWG afterall?
 

n.tesla

SFF Lingo Aficionado
Jul 19, 2020
113
38
It really depends how much juice is running through the cable, for how long and at what length. You could go forth and do the math if the application demands it but honestly 18 awg (0.75 mm² for most people) should be easy to work with and will play nice with a good range of crimping tools.

If you want the cable to 'pad out' your sleeving material then you can opt for UL1015. This spec is rated for higher temperatures (105 °C) and voltages (600 V) and so has a considerably thicker insulation jacket. This way, you can get good looking cables without the headache of trying to work with a guage of wire that's too thick for the application. Due to the increased thickness of insulation, the cable will 'remember' it's shape better
DATASHEET: 0.75 mm² UL1015 Datasheet

The 'standard' spec is UL1007. This will give you moderate insulation thickness as it is rated for lower temperatures (80°) and voltages (300 V). Note that for a PC build, this is of virtually zero significance. The only determining factor here should be aesthetics and malleability.
DATASHEET: 0.75 mm² UL1007 Datasheet

Since you're looking for skinny cables however, you might want to check out UL1061, it has the same temperature and voltage rating as UL1007 but has a much thinner insulation jacket.
DATASHEET: 0.75 mm² UL1061 Datasheet

Have a look at the datasheets to see exact diameters of insulation jackets.
Note that the cable stranded diameter of UL1015 and UL1007 are identical while UL1061 has a slightly increased guage for decreased resistance to maintain the same temperature and voltage rating with a thinner insulation jacket.

I'm yet to actually sleeve my Enhance 7660b but I've done the research, bought the sleeving and the tool (IWISS SN-48B). I can't comment on how it crimps yet but it seems well made and I received a proper machined steel crimp die I ordered seperately also from aliexpress and not the bobbly black metal ones that I assume come out of moulds.

And that's my long winded story about cables that nobody asked for or probably wants, haha, hope you liked it.
 

Arc_Lag

Caliper Novice
Original poster
Jul 2, 2019
32
5
It really depends how much juice is running through the cable, for how long and at what length. You could go forth and do the math if the application demands it but honestly 18 awg (0.75 mm² for most people) should be easy to work with and will play nice with a good range of crimping tools.

If you want the cable to 'pad out' your sleeving material then you can opt for UL1015. This spec is rated for higher temperatures (105 °C) and voltages (600 V) and so has a considerably thicker insulation jacket. This way, you can get good looking cables without the headache of trying to work with a guage of wire that's too thick for the application. Due to the increased thickness of insulation, the cable will 'remember' it's shape better
DATASHEET: 0.75 mm² UL1015 Datasheet

The 'standard' spec is UL1007. This will give you moderate insulation thickness as it is rated for lower temperatures (80°) and voltages (300 V). Note that for a PC build, this is of virtually zero significance. The only determining factor here should be aesthetics and malleability.
DATASHEET: 0.75 mm² UL1007 Datasheet

Since you're looking for skinny cables however, you might want to check out UL1061, it has the same temperature and voltage rating as UL1007 but has a much thinner insulation jacket.
DATASHEET: 0.75 mm² UL1061 Datasheet

Have a look at the datasheets to see exact diameters of insulation jackets.
Note that the cable stranded diameter of UL1015 and UL1007 are identical while UL1061 has a slightly increased guage for decreased resistance to maintain the same temperature and voltage rating with a thinner insulation jacket.

I'm yet to actually sleeve my Enhance 7660b but I've done the research, bought the sleeving and the tool (IWISS SN-48B). I can't comment on how it crimps yet but it seems well made and I received a proper machined steel crimp die I ordered seperately also from aliexpress and not the bobbly black metal ones that I assume come out of moulds.

And that's my long winded story about cables that nobody asked for or probably wants, haha, hope you liked it.
I see! Thank you for the detailed explanation! Do you know a good retailer who sells those kinds of cables? I was thinking of buying from MDPC as they don't have any markings on their cables, but they don't seem to have UL cables :(
 

n.tesla

SFF Lingo Aficionado
Jul 19, 2020
113
38
I see! Thank you for the detailed explanation! Do you know a good retailer who sells those kinds of cables? I was thinking of buying from MDPC as they don't have any markings on their cables, but they don't seem to have UL cables :(
Depends. Where do you live?! Does it matter if the cables have markings? If you're planning on sleeving, then I'd say probably not.
If you're in the UK then check out RS Components. Delivery is free with orders over £30 and it just so happens you can get 100 metres of cable there for £30! That's likely more than you need though so perhaps a 30m spool and think of some other bits you need to make up the difference. Honestly though, as long as the gauge is good, I wouldn't worry about it too much. Can always check out your local DIY shop/garage too.

EDIT: I would add that eBay is a solid option for cable if you need it in low quantities also.

Just don't go spending loads of cash on snake oil /go-faster stripes cable. As long as it has certification, you're golden.
 
Last edited:

Valantar

Shrink Way Wielder
Jan 20, 2018
1,668
1,555
Hey, I've been thinking this whole time and then I saw PSlate, I'm certain that their cables don't use 17 AWG or 18 at that matter, looks more like 23. Can you confirm?


Or am I simply making a mistake and those cables are 17/18 AWG afterall?
Those are likely 18AWG - they aren't the typical PVC insulated cabling, but a type of much thinner, slightly stiffer clear insulation. They're quite common in specialty SFF hardware. It's excellent for slimming down cabling, but it's also quite fragile, with the combination of a small nick in the insulation and some bending potentially exposing the wiring (as the insulation isn't as elastic as PVC). Still, if treated with care those types of wires are excellent, and a great space saving measure.
 
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