Largura de banda:
PCIe 1.x herdado - 250MB / s por pista (16x == 16 pistas)
PCIe 2.0 atual - 500MB / s por pista (portanto, 16x PCIe 2.0 é 8GB / s)
próximo PCIe 3.0 - 1 GB / s por pista
Tamanho físico ( do Wiki ):
The width of a PCIe connector is 8.8 mm, while the height is 11.25 mm, and the length is variable. The 'minor' half of the connector is 11.65 mm in length and contains 22 pins, while the length of the 'major' half is variable. The thickness of the card going into the connector is 1.8 mm.
Lanes | Pins Total | Pins in 'major' half | Total Length | Length of 'major' half
------+------------+----------------------+--------------+-----------------------
x1 | 36 | 14 | 25 mm | 7.65 mm
x4 | 64 | 42 | 39 mm | 21.65 mm
x8 | 98 | 76 | 56 mm | 38.65 mm
x16 | 164 | 142 | 89 mm | 71.65 mm