The PCI Express bus comes in several versions (1X, 2X, 4X, 8X, 12X, 16X
and 32X), which provide throughputs of between 250 Mb/s and 8 Gb/s, or
close to 4 times the peak throughput of AGP 8X
ports. Because its manufacturing cost is that similar to that of the
AGP port, the PCI Express bus will progressively replace the former.