[SOLVED] 6 pin cable needed for GPU, but not supplied with PSU

Jul 5, 2020
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I am building my first PC.

My GPU has a 6 pin and an 8 pin connector which I understand is fairly common.

My PSU has only 8 pin connectors. 2 of them are blue and labeled "CPU" The cables they supplied include 2 that are blue on one end. These are 8 (6+2) pin.

I also have one 8 pin (4+4) pin that I used for the 8 pin GPU connector.

I tried the second 6+2 (with the blue end) to connect the 6 pin connector on the GPU (with the +2 pins not connected to anything) and even though the white light comes on, when that cable is connected, the PSU will not start up. When I disconnect it, it powers right up.

So I think I need an 8 pin to 6 pin cable, but how do I know what the pin out on the cable is, and what I need?

I have the pin outs for the PSU cables, but I have not been able to find the pin out required for the GPU (it is an ASUS ROG Strix GeForce RTX™ 2060 Advanced edition 6GB GDDR6 ).

The PSU is a GameMax 850W Modular RGB Gold 80 Plus

Any guidance would be appreciated.
 
Solution
PSUs come with the cables if they're modular. 6+2 pin are PCIE cables.

Honestly, the next step would be to return the PSU. You made the classic mistake of someone building a first PC. Instead of buying a quality PSU with the wattage output you need, you bought one at a wattage you don't remotely need and then saved money to compensate by going with a cutrate manufacturer.

I'm also extremely concerned because the modular connectors for this PSU, at least on the website, don't have any blue on them. So I'm not sure exactly what you're trying to do. Hopefully it doesn't involve stuffing anything that goes into the CPU area into the GPU, the result of which can range from bad to devastating.

Math Geek

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you have 2 6+2 pcie connectors. that's what you have to use. they are most likely on the same cable. the +2 part means you can split off 2 pins to only use 6 pins if needed.

that's all you need to do to make it work. the other connections are for other parts and WILL NOT work n the gpu nor anywhere else they are not intended to be used on!!

look at your pcie connetors close and you'll see the split where you can take away 2 pins.
 

DSzymborski

Curmudgeon Pursuivant
Moderator
PSUs come with the cables if they're modular. 6+2 pin are PCIE cables.

Honestly, the next step would be to return the PSU. You made the classic mistake of someone building a first PC. Instead of buying a quality PSU with the wattage output you need, you bought one at a wattage you don't remotely need and then saved money to compensate by going with a cutrate manufacturer.

I'm also extremely concerned because the modular connectors for this PSU, at least on the website, don't have any blue on them. So I'm not sure exactly what you're trying to do. Hopefully it doesn't involve stuffing anything that goes into the CPU area into the GPU, the result of which can range from bad to devastating.
 
Solution

Math Geek

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it does sound like you probably have cables in the wrong place which is why it is not working.

the psu itself tells you what cables to plug in where on the psu itself. it has to be done that way. very carefully recheck EVERY power cable and be sure it is in the right place on the part as well as on the psu itself.
 
Jul 5, 2020
5
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you have 2 6+2 pcie connectors. that's what you have to use. they are most likely on the same cable. the +2 part means you can split off 2 pins to only use 6 pins if needed.

that's all you need to do to make it work. the other connections are for other parts and WILL NOT work n the gpu nor anywhere else they are not intended to be used on!!

look at your pcie connetors close and you'll see the split where you can take away 2 pins.

The 6+2 cables I have are both blue on one end. That matches with the blue "CPU" connections on the PSU. I tried these cables in the way that you suggest and they physically fit at both ends, but the PSU does not work when I do that. Seems like the pinouts on the CPU ports of the PSU are different than the pinouts for the accessory ports on the PSU.
 

Math Geek

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that's a pretty poor design if they fit multiple places and multiple ways. if they are pcie, then plug them into the pcie spots on the psu. the cpu cables should go in those slots and so on.

if everything is right and it won't turn on, then the psu itself has problems and may need to be returned. honestly it is not a very good unit anyway. 850 watts is ample for more than one gpu and it should have at least 4 8-pins on it. raidmax is not really known for quality units at all no matter how many stickers they put on the box.
 
Jul 5, 2020
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I agree that my PSU is oversized, and that the one I bought does not have the best reputation, but unfortunately, I pulled the trigger before I researched this PSU. I did a lot of research on the other parts, so live and learn I guess. I was also running into the problem of things being out of stock and I didn't want to wait a month.

In any case. Are you saying that a 4+4 PCI-E should not fit in a 6+1 PCI-E slot? That is basically what is happening. The 6+2 cables I have are for the CPU power. I used one of the 4+4 cables on the 8 pin connector on my PSU and I have one more.

I really think it is just a matter of getting the right cable, but I don't want to hook a cable up with the wrong pin out.

I am an engineer, so I am pretty careful about all of this stuff and fairly savvy, I just made the mistake of being impatient and not doing enough research on the PSU. I appreciate your comments. Always willing to learn.
 
the CPU (4+4) cable is your ATX/EPS cable that should be 8-pin at the PSU side and connect to your motherboard as split 4 or 8

I am building my first PC.

My GPU has a 6 pin and an 8 pin connector which I understand is fairly common.

My PSU has only 8 pin connectors. 2 of them are blue and labeled "CPU" The cables they supplied include 2 that are blue on one end. These are 8 (6+2) pin.

I also have one 8 pin (4+4) pin that I used for the 8 pin GPU connector.

I tried the second 6+2 (with the blue end) to connect the 6 pin connector on the GPU (with the +2 pins not connected to anything) and even though the white light comes on, when that cable is connected, the PSU will not start up. When I disconnect it, it powers right up.

So I think I need an 8 pin to 6 pin cable, but how do I know what the pin out on the cable is, and what I need?

I have the pin outs for the PSU cables, but I have not been able to find the pin out required for the GPU (it is an ASUS ROG Strix GeForce RTX™ 2060 Advanced edition 6GB GDDR6 ).

The PSU is a GameMax 850W Modular RGB Gold 80 Plus

Any guidance would be appreciated.
 
Last edited:
Jul 5, 2020
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4+4 is for the cpu not the GPU. 6+2 is for the gpu and not the cpu.

if the cable fits, it is still not the right connection and will not work. put them in the right place regardless of where else they may fit

If you are correct, that means they color coded the cables wrong and if that is the case, I don't trust their equipment at all. I am going to get a different PSU
 
If you are correct, that means they color coded the cables wrong and if that is the case, I don't trust their equipment at all. I am going to get a different PSU

From looking at the pictures of that power supply the CPU cables are blue and marked CPU on the power supply. The PCI-E slots are also marked on the power supply. If your cable set does not match then yes it's a good idea to return it, but the problem is that currently good power supplies are very hard to find, EVGA SuperNova, Corsair CX, TX, RM models, Seasonic, all are in short supply or at high prices. This model is good, but the price is like $60 over what it should be, when I bought a similar PSU it was on sale and was like $80 https://www.amazon.com/EVGA-Superno...&sprefix=seasonic,electronics,582&sr=1-3&th=1
 

DSzymborski

Curmudgeon Pursuivant
Moderator
In the first local computers store that you will mention the problem, they will offer you the solution, 8 pin to 6 Pin cable for 3$.

At which time you ignore such advice and go with a safe option, having a proper PSU with the proper connector.

Thankfully, as an engineer, Jowin appears to have been trained that insufficient equipment can't be trusted for a safety purpose.
 

Karadjgne

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Has nothing to do with the plastic plug. Has everything to do with WHICH plastic plug.

It's not that hard. OP just needs to actually look at the psu and think about what goes where. The cables marked CPU go to the cpu. That's the EPS power plug at the top left corner of the motherboard. They use a 4+4pin because that's how motherboards are setup, the EPS is either 4pin, 8pin or on some high end boards you'll see 12pin or 16pin, requiring 2x 4+4pin CPU cables.

You absolutely do NOT want to use a $3 adapter to try and plug an EPS/CPU cable to a GPU, they are not wired the same and you WILL put 12v to ground.

The psu side plug is irrelevant. It's just a connection, so it's pin count is basically meaningless as the amperage tolerance is higher than what gets plugged into the other end.

For the GPU, you use the 6+2 end of 2x cables, to the GPU, 1 cable uses 6+2, the other cable uses 6 without the +2. The other end gets plugged into any of the pcie/Sata outlets on the psu.
 

kiriakos-gr

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You absolutely do NOT want to use a $3 adapter to try and plug an EPS/CPU cable to a GPU, they are not wired the same and you WILL put 12v to ground.

Any local PC builder shop, this has has people with enough skills, so them to pass a great advice to their customer.
Additionally they take responsibility for their opinion and offered products, something that does not happen in forums with totally anonymous contributors.
You are entitled just to offer a friendly advice and this is the border line.
 

Wolfshadw

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If you are correct, that means they color coded the cables wrong and if that is the case, I don't trust their equipment at all. I am going to get a different PSU

Amazon Link
If this is your power supply, the second image shows the included cables. The blue ends of the CPU 4+4 cables connect to the motherboard, not the power supply. Why you are given two, I cannot answer.

As otherwise states, the 6+2pin cables are for your graphics card. It appears you have two of those as well. Both need to be connected to your power supply. One of them needs to use all eight pins connected to your 8-pin PCIE power port on your graphics card. The other cable needs to be connected as well, but with the +2 cable hanging free.

-Wolf sends
 

Karadjgne

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Any local PC builder shop, this has has people with enough skills, so them to pass a great advice to their customer.
Additionally they take responsibility for their opinion and offered products, something that does not happen in forums with totally anonymous contributors.
You are entitled just to offer a friendly advice and this is the border line.
I've been building pc's for 40 years, both amateur at home for clients and professionally in shops for clients, and I'll say this about the business, and this goes for most businesses, there's very few people who will say No. You walk in the door, and you will be sold, upgraded, walk out with unnecessary parts and more, because businesses in in it for the money. They only care about you and your buying ability, any honest feelings are kept bottled up. They'll sell you a cheap $3 adapter, tell you it should work, and when it doesn't, or something happens, they'll tell you to bring it in and they'll fix it for a discount. $100 shop fee, 3hrs of labor, and a $20 psu with a $400 bill.

98% of all the regular posters here are not. We are all volunteers, many of us been around for years and have seen it all. We've seen what happens when you use cheap adapters that use 20ga wires, we know what happens when you try to put 150w through a terminal rated for 120w.

As you say, people are entitled to their opinions, but I for one would rather it be an informed opinion than an assumed opinion, or one based on hearsay.
 

Wolfshadw

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Folks, your opinions have been noted. Please keep your comments directed SOLELY towards the Original Poster (OP). No more side discussions about what WE would or would not do. This is now up to the OP. If the OP has additional questions, let him/her ask and then you may answer directly.

Wolfshadw
Moderator.