I've got a r9 270X. My psu comes with a pci e slot that can go into the card. And I got 2 cables from 6 pin to molex. Can I plug that 6 pin pci e into the gxf card and use the other cable to go into a molex?
Exactly which power supply does your system have?
It is not usually a good idea to use molex/PCI-E converters for graphics cards because if the PSU doesn't have the required connectors it usually doesn't have the output to safely run the card.