*** Front and Rear Firewire 400 Ports Share Same Bus? ***

I am wondering if the front and rear Firewire 400 ports are just linked together on the same bus, or do they connect to the CPU on separate channels.
- thanks for any wisdom.
Ted.

You are assuming that the FireWire controller is capable of something I've never seen confirmed, that there is 240MB/sec. And there isn't. I've created RAIDs on multiple FW PCI cards. I've used ATTO SCSI adapters.
And one thing I know about the old G4 was there is a maximum of 240MB/sec for ALL PCI slots that gets shared, not for each PCI slot, though there are adapters like FirmTek's Serial ATA SeriTek controllers which tend to "hog" all the bandwidth and limits the performance of or number of other controllers.
PCI-X was suppose to get past that by providing two buses, one @ 100MHz and the other @ 133MHz that keep them from 'stealing' the others.
PCI Express is an improvement (PCIe 2.0 is beginning to show up) but rarely do buses perform as well as they are suppose to on paper.
That can mean front side bus, memory bus, as well. The G5 memory bus never lived up to its expectations or white paper potential. The Mac Pro seems to have its own memory bandwidth limitations.
And I am not trying to cover up anything. Shed a little light, if not sunshine. More from testing and having talked to developers rather than an engineering background.

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    This does not seem right to me.
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    3) If the iSight works on the rear FW port then why shouldn't it work on the front port?
    4) If an iSight not working on the front port is "normal behavior", then why does it work on the other 6 computers.
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    iSight. Do you have any other FireWire devices to
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