Supermicro Mainboard

If cards not detected on supermicro boards and all LED on the Digital Devices card are blinking, then try following:

Open the BIOS of the Mainboard and navigate to:

Advanced > PCIe/PCI/PnP Configuration > PCI(e) Latency Timer

The standard value should be in the most cases 32 cycles. If you have detection problems on a big number of cards, try to raise up this value step by step.

Also the setting:

Advanced > Chipset Configuration > System Agent Configuration > PEG Port Configuration

Set the slots to PCIe-GEN1 - The cards have now a longer time to answer at the detection procedure (I²C)