RTX 4090 Power Cables

[JT0051]

Just picked up a Corsair HX1500i PSU and an Usus Tuf 4090 OC.

 

4090 requires 4 power cables.

 

PSU came with 3x EPS/ATX12v 8 pin (4×4) cables. And 3x PCle 8 pin (6+2). So not enough of either cable to power the GPU. 

 

The PCle 6+2 cables have only 7/8 pins used on one end (2 wires going into 1 pin).

 

The store I bought them from says I'm OK to use a combination of EPS/ATX12V 8 pin (4+4) and PCle 8 pin (6+2) cables to power the GPU.

 

Just want to confirm this is OK to do? I don't trust all retailers haha so want to be safe.  On my first ever build here...

 

Thanks!

[GuiltySpark_]

No, do NOT try to force one of the CPU 12v EPS connectors in to power a GPU, that will not work. 

 

You have all the cables you need with PCIe. Your PSU came with 3x of each of these. 

 

If you want to truly connect up 4x individual cables (which isn't necessary) you'll use all 3x of the top cables and 1x of the bottom cables and have the little 6+2 hanging free. Some find that ugly so what you can do alternatively, and I promise you this is fine, is use 2x of the top cable and just 1x of the bottom and connect the 6+2 to fill up all 4x connectors on the GPU. 

 

You can always just order a custom cable later if you want to clean this up.
 

[emosun]

the eps 12v and pci-e 12v are different connectors so you'll need 4 pci-e connectors , how old is that power supply ? not when you bought it , but how old is the power supply?

[emosun]

actually according to spec your powersupply comes with 9 pci-e cables , so check the box again

[JT0051]

25 minutes ago, GuiltySpark_ said:

No, do NOT try to force one of the CPU 12v EPS connectors in to power a GPU, that will not work. 

 

You have all the cables you need with PCIe. Your PSU came with 3x of each of these. 

 

If you want to truly connect up 4x individual cables (which isn't necessary) you'll use all 3x of the top cables and 1x of the bottom cables and have the little 6+2 hanging free. Some find that ugly so what you can do alternatively, and I promise you this is fine, is use 2x of the top cable and just 1x of the bottom and connect the 6+2 to fill up all 4x connectors on the GPU. 

 

You can always just order a custom cable later if you want to clean this up.
 

Oops! I did shove a CPU connector into one of the 4 GPU connectors on the bench (Nothing hooked up yet) while I was trying to figure this out. The build hasn't started yet. Now that I look very closely I can see that they do not perfectly match.

 

It's a good thing I didn't trust the store as my gut told me lol.

 

I was going to do 4 cables just because I have seen warnings about doubling up on plugs.

 

As far as I understand 3 cables is good enough for 450 watts and 4 cables for 600 watts.

 

Thanks man appreciate it! Please don't go away haha...

[JT0051]

44 minutes ago, emosun said:

actually according to spec your powersupply comes with 9 pci-e cables , so check the box again

Right, there's 9 in total. As far as I understood it's not good to plug 2 connectors in on one end so I never mentioned those. I see now I just let one plug dangle as GuiltSpark says. PSU is a recent Corsair HX1500i 2022 model.

 

I didn't think this part of the build would be so rediculous lol. Like zero information in any of the manuals about any of this.

[emosun]

1 minute ago, JT0051 said:

As far as I understood it's not good to plug 2 connectors in on one end so I never mentioned those.

well theres 9 cables and you only need 4 so , use 4 of those cables

[GuiltySpark_]

18 minutes ago, JT0051 said:

 

 

I was going to do 4 cables just because I have seen warnings about doubling up on plugs.

 

As far as I understand 3 cables is good enough for 450 watts and 4 cables for 600 watts.

 

Thanks man appreciate it! Please don't go away haha...

There is.. more nuance to all that but yeah, just do that. 

[JT0051]

51 minutes ago, GuiltySpark_ said:

There is.. more nuance to all that but yeah, just do that. 

Being a newb, I will just play it safe and ugly for now lol. 

 

No harm done plugging that CPU cord in? Pins seem fine everything looks OK.

 

Not sure what cords I will need later on in the build for what exactly. So I should have everything I need as far as PSU cords for the entire build?

 

Just one more dumb ass question lol...

 

Does it matter what ends of the cord go into the GPU harness end vs PSU end? Other than the ugly would be better off hidden on the PSU end?

 

Edit: Never mind that last part, is see the PCI connectors also slightly differ on each end and can only go one way. Being a former mechanic and a builder of RC helicopters and airplanes, I'm not used to plugs being so similar-but different.

 

Thanks again. Huge help brother.

[Blai5e]

@JT0051 - just make sure you fully seat the 12HPWR to 4 x PCIE adapter into your graphics card. As you are using the adapter, plug it in before installing the GPU into your case so you can check it is seated correctly. I use a CableMod 12HPWR to 4x PCIE (Corsair Type 4) native cable and I had it plugged in at the GPU end before I installed the GPU into my case (vertically mounted). The adapter that came with my ASUS TUF 4090 OC is still sealed in the retail box.

[Alex Atkin UK]

4 hours ago, JT0051 said:

Right, there's 9 in total. As far as I understood it's not good to plug 2 connectors in on one end so I never mentioned those. I see now I just let one plug dangle as GuiltSpark says. PSU is a recent Corsair HX1500i 2022 model.

 

I didn't think this part of the build would be so rediculous lol. Like zero information in any of the manuals about any of this.

There's nothing wrong with plugging 2 cables in on one end, Corsair rate the cables accordingly at 300W per cable, 150W per connector and in fact their 12pin cables only use two connectors at the PSU end.

If it bothers you, get one of their official cables, they are a LOT easier to cable manage and look a lot neater than the NVIDIA adapters.  They also have Premium cables in different colour combinations which seem to be more readily in stock.

[JT0051]

1 hour ago, Blai5e said:

@JT0051 - just make sure you fully seat the 12HPWR to 4 x PCIE adapter into your graphics card. As you are using the adapter, plug it in before installing the GPU into your case so you can check it is seated correctly. I use a CableMod 12HPWR to 4x PCIE (Corsair Type 4) native cable and I had it plugged in at the GPU end before I installed the GPU into my case (vertically mounted). The adapter that came with my ASUS TUF 4090 OC is still sealed in the retail box.

Yes I am being very carefull with making sure plugs are 100% seated and in the way you said. I know what can happen if they are backed out a bit. Going together pretty quickly actually for being my fist time. 

[JT0051]

40 minutes ago, Alex Atkin UK said:

There's nothing wrong with plugging 2 cables in on one end, Corsair rate the cables accordingly at 300W per cable, 150W per connector and in fact their 12pin cables only use two connectors at the PSU end.

If it bothers you, get one of their official cables, they are a LOT easier to cable manage and look a lot neater than the NVIDIA adapters.  They also have Premium cables in different colour combinations which seem to be more readily in stock.

The cable mess is actually not as bad as I was expecting. But could look more tidy yes. I will look into improvements.  Just want to get up and running for now

[Alex Atkin UK]

25 minutes ago, JT0051 said:

The cable mess is actually not as bad as I was expecting. But could look more tidy yes. I will look into improvements.  Just want to get up and running for now

I wasn't going to bother at first, but very glad I did as its SO much neater.