After watching JayzTwoCent’s recent video, I checked my own Corsair 12vhpwr cables and saw that there were BIG variances in the pins. That worried me a lot, especially since Buildzoid and der8auer have shown how suspect the 12vhpwr cable and connector can be – especially for the RTX 5090.

And while I ‘only’ have an RTX 5080, this is still at risk of melting. So I decided to test out my Corsair PSU and 12vhpwr cables a lot, using a range of testing methods, and I also spoke to Corsair’s director of marketing to get further information.

If you prefer text over video, please read on for the guide/transcript version of this video.

Video Transcript And Guide

Hey everyone, I’ve kind of been feeling like a mad scientist over the past few days because when I received my RTX 5080, I wanted to make sure I had the best possible power supply units for it. So, for my two computers, I ran out and I bought a Montech one and also a Corsair one, and they are both the newest 2025 model ATX 3.1, meaning they got 12V-2×6 slots on it.

In other words, you got a 12V power cable. You plug one end into the 12V D2×6 slot, the ATX 3.1 on the power supply unit, and then the other end into the graphics card. And then I’ve been happily gaming on my systems with no issue at all until I started seeing all of the melting stories of the RTX 5090s but also the 5080s as well.

There have been some brilliant videos by der8auer, JayzTwoCents, and Buildzoid that sort of break things down and show off possible causes or possible things to be concerned about, and also how you can actually check things to protect yourself. And in the process of that, I actually saw JayzTwoCents’ video where he basically showed loads of different 12V power cables. And he picked on Corsair—picked on might be the wrong word actually—but he actually picked out one of Corsair’s cables and noticed that the pins inside of them seem to have quite a lot of variance.

So basically, some pins were quite recessed in the actual plastic housing, and some of them were right up against the actual top of it. And what Jay concluded, or at least asked the experts to chime in on, is whether or not that could actually be an issue. And actually, Jay later on in the video used a clamp meter to check the voltage on all of the Corsair wires, and he noticed quite a lot of fluctuation.

And obviously, that’s concerning because if all the voltage is flowing down one or two wires, and maybe you got a 5090 that’s drawing 600 watts of power, you could potentially get melting issues, as der8auer has actually shown. So that is concerning, and even though I’ve only got a 5080, I wanted to actually test things out and see whether my Corsair cables stand up to scrutiny.

And that’s because when I watched Jay’s video, I actually looked at my own Corsair cables and noticed that the pins are actually quite recessed. But also, you can actually pull the little wires on each individual one, and then the pins move even more. And what’s more troubling is when you actually plug this into your PSU, your GPU, the pins keep moving. So you can actually keep wiggling things, and you wouldn’t really want to do that in general.

But obviously, if you’re cable managing things, then obviously, you know, you could actually inadvertently pull a pin. So I was a bit worried about whether actually that could cause voltage fluctuations too. And so I basically went out and tested everything to see whether I should be concerned or not.

And I also looked at all of Corsair’s responses on Reddit and things like that, where they talk about a 0.44mm tolerance for the pins. And I actually used digital calipers to verify whether the pins are in spec or not. And then I moved on to actually running the system under load, drawing 390 watts with FurMark, and seeing whether there were any issues with the thermals or with the actual voltage running through each wire.

But let’s firstly look at the tolerance, because Corsair seems to mention a 0.44 tolerance. And when you look at the pins here, this is my Corsair 12V power cable. It looks like quite a lot, especially compared to the Montech one. You know, the pins are quite lined up well in the Montech one and then not so much with the Corsair one.

So what gives? Is there a problem? Well, that’s what George, the marketing director at Corsair, actually wanted to address in responding to Jay’s video from before. And he mentioned that there’s a general 0.44mm tolerance in either way because there must be some give and take to make sure that the pins internally can actually bond correctly into the GPU and the PSU.

And then George actually shared this diagram, which mentions 0.55. I’ll talk about that in a second, but essentially showing that from the top, the very topmost, you can have that 0.55mm tolerance. And then, if you look at it from the other side, that adds up then to a 0.99mm tolerance because it’s a plus and minus. So when we talk of 0.44, that could actually be 0.88.

We’ll look at that in a minute, but again, if we go back to one of my Corsair cables, it almost looks like you got some pins that are completely at the top and some which are way down. So it does look wrong and out of tolerance. But this is actually what George told me when I spoke to him directly, the marketing director of Corsair. He told me that actually, they’ve got different tolerances depending on the vendor. Feel free to pause before that goes off the screen.

But one of the other things that George told me via email when we spoke is that actually, the pins do have some level of movement to make sure that the sockets align inside the actual connector because the GPU side is rigid. So that does make sense. And the other reason that Corsair and all the other power cables, for that matter, have some level of variance is that the board partners might have their own variances and tolerances too, because this is a mechanically engineered product. There will be some level of variance.

George also shared these X-rays with me, and it’s really cool to see this because I don’t have my own X-ray machine. But essentially, this is inside a particular connector, and this was actually a cable that they threw out for being out of tolerance. It was over a millimeter, but even then, there was a perfect bond between the pins, and there were no issues with thermals or melting or anything like that.

So that’s reassuring. But I wanted to try it out for myself.

If we were to look at the variance between one of the bottom pins that I can get and one of the top pins I can possibly get, we can then obviously work out whether it’s in spec or not. And to do that, what I’ve done is use a paper clip.

And you know, again, don’t try this at home. What I’ve actually done is, on the topmost pin, which is this one, I’ve put a paper clip in there, and then I’ve actually used the Stanley knife to actually, you know, measure out where it is from the very top.

And the thing is, these pins are not at the very top of the plastic housing. They look like it because this is such a small connector, but they’re actually not completely at the top. From the very top, it does look like you might get something like basically around 0.4mm from the very top, which might be surprising. You might think it’s actually a lot less than that because it does look like it’s from the very top before if I was just to put the calipers against this and actually measure it up or eyeball it, you know.

So, from the very top, it’s around 0.44, which does add up with one of Corsair’s diagrams that I showed earlier. And then, if we actually look at the bottommost pin, and again, I’ve notched this out as well over here, the bottommost pin is this one on the corner. When you look at the pin, it looks like it’s really, really recessed compared to all the rest.

But when you look at it in terms of, you know, a notch on a paperclip or something like that, it’s not actually that much at all. So, we’ve got maybe 0.4 from the top if we look at the other pin. And if we look at this particular one again with that macro lens, I can’t completely show, but I’d say this is around 0.7mm.

Okay, so around 0.7. Again, that could be like 0.74 or something because it doesn’t quite show, you know, the actual hundredths of units. But if I was to go up to 0.8, I think that that’s probably now a bit too much. So, I’d say probably that’s around 0.7.

So really, if we look at the difference of both of them, you probably are looking at around, you know, 0.3–0.4mm between the very top pin, you know, the one I can get up as much as possible towards the top of the plastic housing, and actually the very bottom pin.

And again, that actually adds up completely with what Corsair was saying, which hopefully means there will be no issues with the voltages or the thermals.

But let’s actually try that out.

So, I unhooked all of my Montech PSU cables and I hooked up my Corsair ones as well, such as the CPU, the motherboard, and 12V power. I didn’t bother with SATA fan power or anything like that, but the computer is spinning up there without the chassis fans, as you can see. But everything else is absolutely fine.

And on Windows, what I’ve done is set a power maximum of 108%, so that my power draw was around 390 watts at peak. And you can see the temperatures being quite high as well, regularly above 70°C for the GPU.

And then I switched over to the thermal camera, as you can see there. And actually, it’s kind of hard to see, but there were no issues like der8auer found or anything like that. All of the cables seemed to be fairly well balanced from a thermal perspective, so that’s great.

You know, it’s not like I could see one cable much hotter than the rest, which would suggest, you know, too much power draw from that cable. Everything seemed pretty good, which was good.

So then I switched over to looking at the PSU side. And I couldn’t get the best footage here, sorry, but actually, overall, same story. No major issues on a per-wire basis, everything seemed balanced.

And to be honest, the hottest thing in the computer was the graphics card because I’ve been running FurMark for like half an hour, so that was hotter than the rest. But again, the actual wires were actually fine. It wasn’t like one of them was hotter than the rest or anything like that.

And you can see that in FurMark, the power draw is around 390W, GPU hotspot of 74°C, and, you know, the voltages are good in HWinfo. You can see the input voltage is absolutely fine and stable, no issues whatsoever.

So that’s actually pretty reassuring, to be honest.

The next thing I wanted to do was use my cable clamp to actually check the per-wire amperages. And as a result, I wanted to split the cables into the grounds and the voltages.

So:

  • 5.5 on the first cable
  • 5.6 on the next cable
  • 5.5
  • 5.5
  • 5.57
  • 5.4

No major issues there, so that’s good.

How about the grounds, though?

  • 3.6
  • 3.6
  • 3.7
  • 3.7
  • 3.6
  • 3.65

So, fairly normal as well.

So, what we’re now going to do is do a yank test. In other words, what I’m going to try and do, because there’s variance in actual pins even when plugged in, there’s a very small amount of variance. I wanted to actually try pulling at the pins a little bit and seeing whether that would affect the voltages too.

That is a voltage one.

  • 5.35—is there any wiggle room in that cable? Yes.
  • Okay, so I’m pulling out—5.35.
  • Pulling in—so there’s no change here either when wiggling the cable, which is good.

I did also try on the PSU side as well, which obviously shouldn’t make any difference. But just in case, you know, any of the pins on the PSU side had any different connections inside or anything.

But same story, you know, it was always around 5.55–5.56. I didn’t see any issues on the PSU side either. So actually, all fairly stable. I had no issues at all at any point really with my Corsair testing.

Next, I wanted to test out my Montech PSU, reset things. So these are my 12 volt ones:

  • 5.1
  • 5.7
  • 5.3
  • 5.5
  • 5.6
  • 5.6

Okay fine. Now grounds:

  • 3.2
  • 3.18
  • 3.17
  • 3.3
  • 3.22
  • 3.24

So, everything was similarly good with my Montech PSU, although there was probably slightly more variance on the voltage wires than with my Corsair PSU. You know, there was a lot less variance there.

Again, I don’t think there’s a major issue with either of them, and certainly not with my Corsair one. And, you know, the Montech one as well—the fact one of them was like 5.1 volts, one of them was 5.7 volts—I don’t think it’s a massive issue either.

Because the key thing is, there were no thermal issues or anything else. Everything ran really stably despite drawing almost 400 watts for quite some time, so both PSUs impressed me.

So, that wraps things up, and I’m actually quite reassured.

And hopefully, this video reassures you too if you’ve got a Corsair power supply unit, because I did see some people on Reddit, after watching Jay’s video, they weren’t sure whether to get rid of their Corsair PowerPlay unit or not. But actually, from my own testing, things seemed fairly flawless.

Even though I could wiggle the cables a little bit while it was running—which you shouldn’t do, by the way—that didn’t cause any voltage fluctuations or anything in my testing, so that’s pretty good.

I hope you enjoyed this video. But if you got any questions, please let me know down in the comments. And other than that, please click the thumbs-up button and subscribe to see more videos like this.

Thanks for watching.