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How to connect my graphics card to my PSU?

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#1
I was wondering how to better connect my new graphics card to my EVGA SuperNova 650W G2 PSU (https://www.techpowerup.com/reviews/EVGA/SuperNOVA_G2_650/). Until recently I’ve used Asus ROG Strix GTX 970 OC graphics card that had single 8-pin power connector and there was no question of how to connect it. Now I bought Asus ROG Strix RTX 2070 OC 8 GB Gaming graphics card that has one 6-pin and one 8-pin power connectors. This card also has two 4-pin PWM fan headers and an addressable RGB header. The recommended PSU power for this graphics card is 550w. This graphics card will be installed on Asus Maximus VII Hero motherboard with overclocked Intel Core i7-4790K CPU.

What is the optimal way to connect this new graphics card to the PSU? It’s probably worth noting that I also plan to overclock this graphics card. The PSU has two connectors for graphics card(s) marked as VGA1 and VGA2. I assume this PSU is capable of powering two graphics cards. Should I use a single 6-pin + 8(6+2)-pin PCI-E VGA cable or two of these cables and connect one of them to 6-pin connector and the other to 8-pin connector? If you recommend using two of these cables, does it matter if I plug 6-pin or 8-pin end of the cable to card’s 6-pin connector? Strangely enough, only 6-pin extension is equipped with capacitor. From all I’ve read and saw so far the conclusion is to use two separate cables as they will give more stable and cleaner power. On the other hand, this will create a cable mess as each cable has a 6-pin extension. Will it cause any damage to my graphics card or PSU and will it affect the performance if I connect them with a single cable?

Thank you in advance!
 
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#2
You can use a single cable if you have both 6 and 8 pin connector on it to keep cable mess to a minimum as your psu has a single 12v rail so it doesn't matter
 
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#3
Using two cables instead of one will result in a better connection between the power supply and graphics card. That said, using a single cable is perfectly fine since it is rated to provide that kind of power.

I use two cables if I can but that's just me.

The cable capacitors should still work even if you connect your graphics card at the 6+2 pcie connector that's in the middle of the cable and before the capacitor.
 
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#4
I have a 6 and a 8 pin connector on a single cable, and it works like a charm.
 
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#5
I asked EVGA the same question and their answer was a bit convoluted: “You would use two separate cables 6+2 with only the 6 connected and a 6+2 or 8 pin connected to the 8pin port.” Even considering the results of this experiment (
), I wonder why bother with two separate cables if gain is so tiny? In view of these findings I would prefer to keep cable clutter to a minimum.
 
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#6
About 1.5% difference in benches in that video which is well within the margin of error and could be down to the restart required between benches, to put it plainly there's no reason with a decent enough power supply to run 2 separate cables for a single gpu, it makes no difference
 
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#8
Do you think I'll have enough power from one cable to overclock the card?
Yes.
You have a single rail anyways.
The only difference in using 1 or 2 cables is you get a little more heat on the single cable from the extra amperage... But nothing to worry about.
 
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