[rescue] SBus vs. PCI

[Gregory Leblanc]

On Fri, 2002-02-22 at 15:24, Dan Debertin wrote:
> James Sharp writes:
> 
>  > All on a couple of FastE sbus cards - no superduper 66Mhz 64Bit
>  > ultrasuperwidebanzaioverclocked PCI.
> 
> That's something I've been meaning to ask about for some time. I get
> the feeling from some people on this list think that the move from
> SBus to PCI was a bad idea for Sun. I've even heard this sentiment
> from current & former Sun engineers.
> 
> What's the technical reason?

Technical reason?  I'll be damned if I've ever heard one.  Some people
just don't like moving forward.  Hmm, let's see.  
SBUS was Developed by Sun, is IEEE P1496, and goes up to 64-bit, 25MHz =
200MegaBytes/sec (standard is only 32-bit/25MHz)
PCI was Developed by Intel, isn't a stanrard, and goes up to 64-bit,
66MHz = 528MegaBytes/sec. 

I'm not sure that I've seen any machines that take 64-bit SBUS cards. 
That makes adding gigabit ethernet rather challenging, since a single
card should be able to saturate the bus.  The Ultra-160 SCSI spec would
be up in that range too.  The new FC-AL is the same bandwidth as 32-bit
25MHz sbus.
As somebody else said, the biggest thing in favor of PCI is the
proliferation of cards.  How else would you get UW SCSI into your U5 for
$60?
	Greg

-- 
Portland, Oregon, USA.