[z4y5f3]

Depends. NVLink advertises bidirectional bandwidth, whereas PCIe and standard networking calculate bandwidth in a single direction. So a 1800 GBps NVLink is actually 900 GBps in PCIe and standarding networking terms.

Therefore, a 512 GBps PCIe would sit between the current H100 NVLink (450 GBps) and next generation B200 NVLink (900 GBps). With that being said, NVLink still has lower power draw and smaller chip area, so it would still have a competitive advantage even if the bandwidth is similar.

[nsteel]

I think you've mixed your Bytes and bits here. Not sure where the power and area numbers come from but I'd expect NVLink to be worse on both counts for similar bandwidths since they shipped much, much earlier.

PCIe 7.0 is 512GB/s and not 512Gbps. 512GB/s is the full-duplex bandwidth. It sits between NVLink2 and NVLink3.

I gave a fuller breakdown in a sibling thread.

[z4y5f3]

Checked your numbers in another thread - excellent breakdown. Thanks for the clarification.

I did not read the original anandtech post so I did not realize the 512GBps already refers to the full-duplex bandwidth. You are right that PCIe 7.0 x16 sits between V100 and A100 NVLink.

[anonymousDan]

Wut, I did not know that regarding NVLink marketing gimmicks! Thanks for the info.