28 Oct
2001
28 Oct
'01
8:57 a.m.
Here we go ...
see below, plz.
Dick
----- Original Message -----
From: "Eric Dittman" <dittman(a)dittman.net
To: <classiccmp(a)classiccmp.org
Sent: Sunday, October 28, 2001 12:52 PM
Subject: Re: VLB SCSI?
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.
ALPHA boards aren't relevant any longer, are
they?
> --
> Eric Dittman
> dittman(a)dittman.net
> Check out the DEC Enthusiasts Club at http://www.dittman.net/
> A typical example is the 64-bit PCI. I've
seen several desirable cards
offered
> for the 64-bit PCI, yet I've not seen even
ONE advertised motherboard that
> actually supports 64-bit PCI. From what I've read, 32-bit PCI boards work
in a
> 64-bit slot, yet nobody seems to be offering that
feature in their
> advertisement. I'd guess that's because it's cheaper/easier to diverge
slightly
from the
published standard in making these products, hence they don't make
claims about compatibility.
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.
As for motherboards with 64-bit PCI slots, there are several. First off,
there
are several Alpha motherboards with 64-bit PCI slots.
Then there are the
boards
for the Pentium III processors with the Serverworks
chipsets. There are also
motherboards for Athlon-MP processors with 64-bit PCI slots (some of which are
also 66MHz slots). I know there were earlier motherboards for Pentium II and
Xeon processors with 64-bit PCI slots, but they weren't advertised in the
usual
places as they were more of a specialized board, but
they were advertised in
some areas.
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.