to quote the wonderful Wiki:
quote:
Originally posted by Wikipedia
The PCIe link is built around a bidirectional, serial (1-bit), point-to-point connection known as a "lane"
At the electrical level, each lane utilizes two unidirectional low voltage differential signaling (LVDS) pairs at 2.5 gigabaud. Transmit and receive are separate diff-pairs, for a total of 4 data wires per lane.
A connection between any two PCIe devices is known as a "link", and is built up from a collection of 1 or more lanes. All devices must minimally support single-lane (x1) links. Devices may optionally support wider links composed of 2, 4, 8, 12, 16, or 32 lanes. This allows very good compatability, in two ways. A PCIe card will physically fit (and work correctly) in any slot that is at least as large as it is (e.g. an x1 card will work in an x4 or x16 slot), and a slot of a large physical size (e.g. x16) can be wired electrically with fewer lanes (e.g. x1 or x8; however it must still provide the power and ground connections required by the larger physical slot size). In both cases, the PCIe link will negotiate the highest mutually supported number of lanes.
Source:
http://en.wikipedia.org/wiki/PCI_Express
what i take from that is that the x1 means it has 1 lane open, and the x16 means it has 16 open, etc etc?
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