Question Comp will not post with graphics card in 16x slot but will in 4x slot

[FatTaylor]

Hi,

I just got a Gigabyte B450M DS3H Motherboard, a long with a ryzen 2600x

I have a GTX 780. When the 780 is in the 16x slot I get 1 long and 3 short beeps for video card error. When I put the same card in the 4x slot, I get into the BIOs just fine. I made sure that the card does still work on my old computer as well.

What could be causing this?

Thanks

 

[rgd1101]

bad motherboard, or bend pin