AMD Prepares USB-C Linux Driver Support For Radeon Graphics Cards

[raun0]

There is a draw back.

which is?

[oiaohm]

which is?

Read the rest of the post. The draw back is the extra consume of PCIe lanes. Just becuase a card is in a PCIe x16 slot does not mean it can in fact use 16 PCIe lanes. You can put a PCIe x16 slot on something and have only 1 lane populated by hardware.

There are quite a few motherboards where you have a PCIe x16 slot but it only has 8 lanes of PCIe in it.

Please note some of AMD PCI 4.0 GPUs have a PCIe x16 on card but only 8 PCIe lanes are in fact wired up. These cases the GPU absolutely cannot use more than 8 lanes of PCIe. Yes these cards perform badly in PCI 3.0 motherboards/slots.

If you are trying to max out what you can do you don't want to be allocating 16 PCIe lanes to something that does not need them and is never going use them. It quite possible that PCI 4.0 and newer GPUs don't need 16 Lanes any more and will not gain anything from having 16 lanes.

The draw back is being wasteful and being able to connect less hardware due to how you allocated your lanes.

amd b550 bifurcation allows you to split 16 lane GPU slot into 2 8 lane slots that physically might look like a PCIx16 slot but only have 8 lanes connected and connect 2 GPUs.
Do note that bifurcation support allows you to pass those 8 lane groups though to different VMs.

So should the PCI x16 slot with all 16 lanes populated with PCIe 4.0 and newer always support a riser card to bifurcation this slot to allow more hardware to be connected.

The question still remains what do we have that really requires 16 lanes of PCIe 4.0 or newer. its not GPUs. Ultra high speed storage devices that home users cannot afford?

Remember 8 lane PCI slots on motherboards can be 16 lane slot in physical dimensions.