On Oct 18, 2007, at 10:43 PM, Kauffman, Tom wrote:
The PCI bus on a P5 will saturate at 400 MB/Sec; you'll need to go to the P6 to exceed that. That, and the $8,000 per end cost are the reasons I have 4 independent gigabit backup networks. (At the lat time I looked, the IBM card was $8,000 and a populated 8-port board for our Cisco switch was $64,000, with the per-port cost getting uglier as you cut the ports down).
Configuring a computer can involve a lot of art and science. What co- resides on the bus can greatly influence the throughput of what you thought would be a very fast interface care. For example, PCI-X buses run only as fast as the slowest device on the bus; and they run at half-duplex. PCI-Express, a wholly different animal, is architected for serial transmission, rather than the horse-race parallel of its predecessors, and runs full-duplex. And, a given computer may contain two different bus types, to accommodate technology transitions in force at the time of design. Many are the factors in what your computer can do for you, and where mysterious performance drags come from. Richard Sims
