But actually looking things up, I see that PCI-Express has a theoretical 8
Gbit/sec, or about 800Mbyte/sec. It's PCI-X that's 533 MByte/sec. So there's
still some headroom available there.
See here for the official specifications of both: http://www.pcisig.com/specifications/pcix_20/
Note that PCI-X version 1.0 at 133MHz runs at 1GB/s. It's a parallel bus,
64 bits wide (8 bytes) and runs at 133MHz, so 8 x 133 ~= 1 gigabyte/second.
PCI Express with 16 lanes (PCIe x16) can transfer data at 4GB/s. The Arecas
use (PCIe x8, see here:
http://www.areca.com.tw/products/html/pcie-sata.htm), so they can do 2GB/s.
- Luke
