Question PCIe 4.0 x8 vs PCIe 3.0 x16

[p1esk]

If I plug a PCIe 3.0 x16 GPU card into a PCIe 4.0 x8 slot, will I get PCIe 3.0 x16 or x8 speed?

 

[rgd1101]

which motherboard have pcie 4.0 x8 slot?

 

[kanewolf]

If I plug a PCIe 3.0 x16 GPU card into a PCIe 4.0 x8 slot, will I get PCIe 3.0 x16 or x8 speed?

You will PCIe 3.0 x8. The slot will slow down to 3.0 to match the card.

 

[p1esk]

ASRock TRX40 CREATOR - I will be using four Quadro 8000 cards in it.