Question 8 pin PCIe doesn't fit PSU or GPU?

KGRGamer

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Hello, please go easy on me as I haven't been into PCs or hardware for 10 years and I'm slowly learning everything from the beginning all over again. I've scoured the forums but can't figure this out.

I have a new GPU that I'd like to connect and I've bought an 8 pin PCIe cable to do this, I assumed they were universal. PSU was second hand so didn't have the ones that came with it at hand. It is not a Corsair PSU. On one side there are two 6+2 connectors that have keyed slots. One the other end is a complete non-split 8 pin connector that doesn't have the keyed thing. My issue is that the complete 8 pin connector, which I assume is for the PSU, will not fit into the PSU, it slides in and the remaining 30% refuses to go in, even with force. Meanwhile the 6+2 connectors on one end fit both the PSU and the GPU. The complete 8 pin does not fit the GPU whatsoever. Am I doing something wrong here as I'm incredibly confused, I feel like I must be missing something very basic here or I've bought a non-compatible cable. I essentially have one side that is unusable with both the GPU and the PSU. Pictures are attached below.


Below is the complete 8 pin. Doesn't have the keyed notch, has one pin missing strangely. Doesn't fit either end.
GBmNZda.jpg



Below is one of the 6+2s, has the little notch. Fits both ends fine.
2oKWZJP.jpg
 
PSU cables are not universal. The 6+2 pin will fit most any GPU; however, the other end of the PSU cable fits particular PSUs. They vary from make and model. It is appropriate to get the proper cable direct from the PSU manufacturer.
 

KGRGamer

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PSU cables are not universal. The 6+2 pin will fit most any GPU; however, the other end of the PSU cable fits particular PSUs. They vary from make and model. It is appropriate to get the proper cable direct from the PSU manufacturer.
Its a Riotoro PSU, they don't appear to stock or sell cables, I believe I'll have to get a Seasonic cable as that's who they're made by. With some further forcing I managed to get it in so there's only about 20% exposed, is it safe to use? What are the dangers of slightly loose connections?

I unplugged an 8pin connection that was already in the CPU and fits in nicely, they seem to have different shaped pins. Top right corner pin is square on the working existing one, whereas it is a hexagon on the one I just purchased. Second from top left on the new one is halfway between a square and hexagon whereas it is a hexagon on the existing one.
 
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You are taking a huge risk doing this. Be happy if it doesn't fit that is a warning you should not do it.
There are many cables that fit perfectly between different brands of power supplies but then destroy the computer or video card etc that you plug them into.

Now you might get lucky and since there are 12 volt and ground pins. Problem would be if somehow they got swapped and you connected a ground directly to a 12 volt pin on the motherboard. You are going to fry the power supply and maybe damage the motherboard. You have a direct short.

Main rule is never use cables that are not for exactly that model of power supply. Now if you can use a multimeter you can likely either build your own cables or validate that a different cable will work.
 
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KGRGamer

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You are taking a huge risk doing this. Be happy if it doesn't fit that is a warning you should not do it.
There are many cables that fit perfectly between different brands of power supplies but then destroy the computer or video card etc that you plug them into.

Now you might get lucky and since there are 12 volt and ground pins. Problem would be if somehow they got swapped and you connected a ground directly to a 12 volt pin on the motherboard. You are going to fry the power supply and maybe damage the motherboard. You have a direct short.

Main rule is never use cables that are not for exactly that model of power supply. Now if you can use a multimeter you can likely either build your own cables or validate that a different cable will work.
Point taken, I'll avoid this cable and see if I can return it. They seem somewhat sleazy so I'll doubt I can get my money back. I just hope I haven't damaged anything by mushing and forcing connectors around.

I'm not sure what to even do now. I'm worried that even using a Seasonic cable on this may not be compatible either, have I essentially been forced into purchasing a new PSU? Riotoro website looks sketchy, I doubt they have any sort of customer service.
 
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DSzymborski

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Point taken, I'll avoid this cable and see if I can return it. They seem somewhat sleazy so I'll doubt I can get my money back. I just hope I haven't damaged anything by mushing and forcing connectors around.

I'm not sure what to even do now. I'm worried that even using a Seasonic cable on this may not be compatible either, have I essentially been forced into purchasing a new PSU? Riotoro website looks sketchy, I doubt they have any sort of customer service.

Basically, you have to know *specifically* that a specific power cable works with the *exact* PSU. Not just the brand, either.

If you can't find a cable that you know *for a fact* works with this *exact* PSU, you're either getting a new PSU or you're playing Russian Roulette. The consequences are significant in the sense that a GPU can very easily be fried and it's something we've seen with people who do this here a bunch of times.
 
Your first option is to check out one of the companies that manufacture third party cables. These are most done for appearance reasons...ie you want you cable white rather than say black. It just depends if they have information on your power supply pinout. If anyone does these type of companies would be the most likely to have documentation. These cables are expensive because they are basically custom made but it will be cheaper than a new power supply.

If you have a multimeter and know how to use it you could consider building your own cable. The end that goes to the motherboard is standard so that is easy to find. The end on the power supply you should be able to test and make a end that fit and is hooked to the proper pins. Although there are 8 pins the ones that power the motherboard are 4 12 volt ones and 4 grounds. This is mostly being careful and testing all the pins on the power supply and making sure they pass though to the correct pins on the motherboard side.