Comment Re:GT/s ? (Score 1) 37
GT/s is not marketing fluff at all, really, and not started by just DDR folks. The term is used to unambiguously describe the base line rate of a channel. It has concrete definitions for the folks actual designing the PHYs on the bus. GT/s as base unit has been in every PCIE spec from at least 1.0 (and probably before). It's used to describe line rates for many channels, not just those used in PCIE. (i.e. DDR, various SERDES, etc. )
A single channel (or lane, or X1) PCIE Gen 8 device will have 256 GT/s * 1 channel = 256 Gbps (raw rate)
PCIE Gen8X2 will have 256 GT/s * 2 channels = 512 Gbps (raw rate)
Similar math for PCIE Gen8x4, Gen8x8, and Gen8x16
These are all raw rates that don't include and line encoding, nor various packet overheads.
The raw rate is an important design consideration for PHY designers, thus having a concrete definition is important for a formal specification. GT/s is commonly used in such standards.