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by tux3 880 days ago
The PCIe standards kept moving to longer codes, and nowadays they're able to do "1b/1b" (no header at all)
1 comments

Not really accurate. The switch from NRZ to PAM4 actually massively increased the bit error rate. They switched away from the 8b/10b style line code and replaced it with forwards error correction.

PCIe 6.0 uses 256 Byte frames, with 242 Bytes of data, 8 Bytes or CRC and 3 Bytes of error correction.

So it actually has way more overhead than the older versions and their 128b/130b line coding, It's just at a slightly different layer.

Thanks! Did not know they added FEC, that makes more sense :)