RM1000X PCIe cable help

[RayRson]

Hello, 

I have a RM1000x 80+ gold PSU  and an 7900 xtx. With my power supply, I was given there PCIe cables with 2 bits that split at the end of them (pigtails???). Is it alright to use 1 cable and half of another cable. I've seen posts about not to use dual cables because it can mess things up. Don't want to somehow damage my expensive GPU. These are the only PCIe (3, all the same) cables I was given. Advice would be much appreciated because I'm scared to plug them into my GPU. Or is there some other correct way of doing this? My GPU has 16 pins or 3 x 8 pins. Sorry I am noob. Or is there a way to buy 3 compatible SINGLE CONNECTORS PCIe cables that will work fine with my system and where can I buy them (link of some kind), thanks to anyone that can help me.

[NiJo]

Did you solve this as I am there now and not sure if I need to go buy another one of the 8 pin singular cables or if I can use one of the splitter cables

[c-attack]

You can use a 6+2 to fill an 8 pin PCI-e power need, but you don't use a double 2x8 connector on a single cable to your GPU.  You haven't specified what GPU you are using, but at 300-600W this is where things can go badly.  If your GPU is 3x8 on the side, you need 3 separate 8 pin (or 6+2) cables.