Originally Posted by Derek_HTPC
Each HDHR only sends 2 channels, so if the HDHRs are connected to a gigabit switch, then each pair of channels will have a dedicated 100Mbps in to the switch. However, from the switch to your desktop you would need gigabit since that would be carrying all the channels. Most modern motherboards now include gigabit, but if not you can add it for $20-40 (a PCIe, not PCI, card is recommended to keep CPU utilization low).
that's the THEORY. but I doubt its really how it works.
desktop gig-e chips are usually crap. seriously. they don't do a great job on latency or sustained thruput on back to back packets.
a good solid 10/100 chip (intel eepro100, for example) CAN keep up and doesn't fall down on the job.
what good is it to clock at gig-e speeds (the chip) and yet drop packet after packet?
my gut feeling is to use dual rail ethernet 10/100 (or even a junky gig-e - but use TWO of them) and feed each hdhr to its own private port.
switches aren't the solution. they will buffer and delay the packets so that they fit 'single file' in the single ethernet stream, out of the switch.
(I saw the same kind of effect on other networking technologies. when laptops were first boasting about 10/100 - but could NOT keep up with a true 100mbps stream (pcmcia laptops, I'm talking about here) - it was a joke! a sad joke. yes, the card could HANDSHAKE and signal at 100meg speeds but the packet loss made things worse. I solved the problem (at my company) by forcing the managed switch to 10mbps speed even though the NIC card 'said' it wanted 100. and when I admin forced the port speed to be 10, we had happier users since a constant 10 was WAY better than a bursty lossy 100. see my point? its not how many PDUs you get thru but its how many MAKE it thru without timeouts, retries, collisions or crc errors.
you care about effective thruput, not line rate clocked speed.
its just my experience that you need a server class mobo to really have a DECENT gig-e implementation. almost always that's pci-x and perhaps lately its pci-e, but NOT the one-chip wonders we see on our $100 mobos.