> > 64-bit PCI cards will work in a 32-bit PCI slot. I've got a four-port 64-bit
> > Ethernet card in a 32-bit PCI slot in one of my systems.
> >
> I really don't see how they could work, since the connector is not likely to
> fit. I recently had a peek at the standard for PCI, and I didn't seen any way
> in which this could work.
They have been designed from the start to be forward- and backward- compatible.
The 64-bit has a slot where the end of the 32-bit connector is located, and the
correct connector does not have a wide end. All the 32-bit connectors I've seen
have been the correct size (and I've seen a lot of them). A 64-bit PCI card in
a 32-bit slot steps down to 32-bit transfers. A 66MHz card in a 33MHz slot steps
down to 33MHz.
> Since there apparently aren't any serious SCSI boards being made for 32-bit PCI
> any longer, and since most fibrechanel and firewire boards are 64-bit, I'd think
> it desirable to have most PCI mothers support the 64-bit PCI, which, according
> to what I've read so far, does support the 32-bit cards. If you want the 250+
> MBPs transfer rates, no short PCI slot is going to handle that. The 10Gb
> ethernet will demand that the system process sustained, meaning for years and
> years, not just for bursts of a few hundred picoseconds, transfer rates of
> 10Gb/sec, and who knows what will come along after that. What's more, it's got
> to work faster than all that at the system level, since the traffic has to go
> somewhere and the responses have to come from somewhere as well.
I've seen 32-bit FC and firewire cards. I've seen FC cards that come in both
32- and 64-bit configurations, although the 32-bit cards I've seen look like
they are the 64-bit version with only a 32-bit edge connector.
I've never seen a 64-bit firewire card.
> ALPHA boards aren't relevant any longer, are they?
I think so. The Alpha will be around for a while, with EV7 on the way, despite
what some people think. Compaq announced the Alpha would be winding down, not
stopping dead in its tracks.
--
Eric Dittman
dittman_at_dittman.net
Check out the DEC Enthusiasts Club at http://www.dittman.net/
Received on Sun Oct 28 2001 - 18:34:59 GMT