|  |     Re .2, generally speaking...  this is in response to the question
    "what's the difference [between primary and secondary PCI buses]?"
    
    Certain PCI adapters do not work properly when configured on n/th-dary
    PCI bus (other than primary) due to a number of different reasons. 
    Sometime it was because the device driver makes a bad assumption that
    the device is only configured on the primary PCI bus (#0), thus not
    looking for the devices on other PCI buses; or, due to incompatibility
    of the PCI bridge chip (being used to tie the buses together), certain
    PCI signals and data are not being forwarded (in either direction -
    to/from the system); or, other variations of the above.
    
    When a PCI adapter and associated driver have been qualified/verified
    to work properly on multiple PCI buses, it should not matter which bus
    it is on.  There have been discussions about performance, e.g. farther
    bridged PCI buses may create longer signal delays - but unless the I/O
    option in question is dealing with a hardware interface that can handle
    "fast" throughput, it'd tend to be an academic discussion.
    
    --svb
 | 
|  |     From the SOC, the only current 2100A slot restrictions are as follows:
    
    KZPSA-BB 3 max for WNT, PB2GA-JB for WNT, and CCMAA-AA/BA mem channel
    for dUNIX.
    
    These are restricted to primary slots, and cannot be installed in PCI slots
    4,5,6 and 7 (THE ONES BEHIND THE BRIDGE).
    
    The DE435-AA is not restricted, and may be placed in any PCI slot.max
    qty is 4.
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