Hi Mak,
Yes, the 32Gbps is correct, and it certainly cannot support 48-port 1000BaseT in a non-blocking fashion. On that note, we don't actually offer a 48 port gig card that is fully non-blocking.
You can think of the sup32 as positioned between the sup1a and the sup2 in terms of system performance, the main reason being that the sup32 has no support for a switch fabric module.
HTH,
Bobby
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