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How to connect this power supply to my graphics card

Last response: in Components
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December 13, 2012 10:33:27 PM

I have recently bought all the components for my new build and two of the components are the cooler master gx 650w power supply and the xfx hd 7870 dd graphics card.

Now the graphics card needs two 6 pin connectors to power it and the power supply was advertised to have two 6+2 pin PCI-e connectors so that's all good.

However, after all the parts arrived I've discovered that these two 6+2 PCI-e connectors are on the same cable.

So my question is even though the two connectors are on the same cable can I use them both to power ny graphics cars?
a b ) Power supply
a b U Graphics card
December 13, 2012 10:40:11 PM

Thats just plain retarded of them to do that. Order a molex to pcie power adapter.
December 13, 2012 11:31:08 PM

I think that's what I'm going to do. So would I not be able to use both of the PCI-e connectors at the same time if they're both on the same cable?
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a b ) Power supply
a b U Graphics card
December 13, 2012 11:35:28 PM

you could probably get away with it as that card is like 130w but the idea of the two connector was to split the load and not overheat the connector or wires. Putting them both on the same rail takes the riskoff the connecotr and leaves it on the wiring? Does the wiring seem thicker than a regular psu?
a b U Graphics card
December 13, 2012 11:36:58 PM

it should work the way it is.
a b ) Power supply
a b U Graphics card
December 14, 2012 12:02:28 AM

Best if you can take a picture of the connectors...
a c 243 ) Power supply
a b U Graphics card
December 14, 2012 12:03:27 AM



December 14, 2012 6:38:31 AM



i wouldn't say they are much thicker than your average psu cables.
a c 243 ) Power supply
a b U Graphics card
December 14, 2012 9:08:57 AM

Jeditiger said:
Thats exactly what i was looking to do. Have you had any problems connecting your graphics card on one cable?

No, and it uses a good deal more power than a 7870

http://www.techpowerup.com/reviews/AMD/HD_7850_HD_7870/...

This has been discussed before, a 6 pin connector is capable of providing much more power than the 75 watts that PCI SIG rates it for, the engineers who design power supplies know this
Dual connector configurations can be found on power supplies that run the range from Dell oem to high end Antecs and Silverstone's
December 14, 2012 9:57:59 AM

delluser1 said:
No, and it uses a good deal more power than a 7870
http://i1081.photobucket.com/albums/j351/contrvlr/7850power_peak_zpscc37f457.gif
http://www.techpowerup.com/reviews/AMD/HD_7850_HD_7870/...

This has been discussed before, a 6 pin connector is capable of providing much more power than the 75 watts that PCI SIG rates it for, the engineers who design power supplies know this
Dual connector configurations can be found on power supplies that run the range from Dell oem to high end Antecs and Silverstone's



Thank you thats exactly what i wanted to know! My only concern is this email i just received from cooler master.

"Dear Josh,

It’s possible but it’s not recommended. Please let me explain.

Your GPU uses (when it’s pushed to the max) 300W of power. Your motherboard delivers 75W (maybe higher for new PCI 3.0 but I’m not sure about that) which means the PCI connector has to deliver 225W. Because the PCI connectors are on the same cable this 225W has to be divided over three strands (three yellow cables). That is 75W per strand; 75W / 12V = 6,25A per strand.

6,25A per strand is really high and the cables will become really hot! Because the cables are bundled together they are not properly cooled and this might become a risk factor.

In general the VGA card doesn’t continuously run at max but it’s still a lot of power for just three strands. We therefore not recommend using just one cable. If I look at the rest of the system we would suggest a better PSU which would have an option to use multiple cables."

I understand what he's saying but even if i overclocked my gpu would it ever get close to the 300W he's suggesting it uses?!
a c 243 ) Power supply
a b U Graphics card
December 14, 2012 10:35:52 AM

Jeditiger said:
Thank you thats exactly what i wanted to know! My only concern is this email i just received from cooler master.

"Dear Josh,

It’s possible but it’s not recommended. Please let me explain.

Your GPU uses (when it’s pushed to the max) 300W of power. Your motherboard delivers 75W (maybe higher for new PCI 3.0 but I’m not sure about that) which means the PCI connector has to deliver 225W. Because the PCI connectors are on the same cable this 225W has to be divided over three strands (three yellow cables). That is 75W per strand; 75W / 12V = 6,25A per strand.

6,25A per strand is really high and the cables will become really hot! Because the cables are bundled together they are not properly cooled and this might become a risk factor.

In general the VGA card doesn’t continuously run at max but it’s still a lot of power for just three strands. We therefore not recommend using just one cable. If I look at the rest of the system we would suggest a better PSU which would have an option to use multiple cables."

I understand what he's saying but even if i overclocked my gpu would it ever get close to the 300W he's suggesting it uses?!

Guess it might if you overclocked the snot out of it, if you were a world class overclocker you probably wouldn't be here asking questions or using a CM GX
Take a look at the max power chart in the review link, see where the 570 sits
!