Question ASUS Prime X299-A PCI and GPU Issue


Jul 14, 2015
MOBO: Asus Prime X299-A
GPU: Asus ROG-STRIX-RX580 (also NVIDIA Quadro K1200)
MEMORY: Corsair Vengeance LPX 64GB DDR4/1/35V
PROCESSOR: Intel, Core i9-9820X 4.1GHz

Hello, I'm building a new system and I've run into an issue with PCI Slot 1 on an ASUS PRIME X299-A. Video cards are non-functional when in Slot 1; but they're fine in the other 16 Slot. Tested with ROG-Strix-RX580 and NVIDIA Quadro K1200; tested with multiple cables too. Cleared CMOS; flashed BIOS to 3006 - no change. I've been researching and can find several references to the same issue on other forums - but, no solution. Not sure if I have something set wrong in the BIOS, or if the PCI Slot is just DOA. Has anyone else had trouble setting up a X299-A?

EDIT: I just tested a PCIe ASMedia eSATA expansion card in PCI Slot 1 - and, it worked just fine. So, the PCI slot is okay. It just won't work when a graphics card is inserted (?)
Last edited: