Hi, if i use any of the pci-e power cables from the other psu on my current computer, if only to run 1 card, it wont start. I cant use molex as i would need 4 connectors to run 2 molex adaptors, and i only have 3 of those flat connectors. I tryed running only one card with 1 pci-e cable of the ones alrdy connected to the psu, and 1 molex adaptor, that did not work either. (the connectors had cables running to casing fans aswell in between). But if i run 1 card with both of the non removable pci-e power cables, it works fine. The Psu is 750w silver power. Im also running 3x 2tb harddrives and 1x ssd, and a creative soundblaster z. But i tryed dissconnecting everything but the SSD harddrive, and it still wont boot with the extra pci-e connectors(the modular ones? If thats what they are named when u can just insert them into the psu) I think the other pci-e power cables is from a gold power 850w something psu i had some years ago.