Subject: Re: Memory: Parity vs ECC?
To: Michael Kukat <michael@bsdfans.org>
From: Wilko Bulte <wkb@freebie.xs4all.nl>
List: port-alpha
Date: 12/30/2002 12:54:21
On Mon, Dec 30, 2002 at 11:32:07AM +0100, Michael Kukat wrote:
> Hi !
> 
> On Mon, 30 Dec 2002, Pavel Cahyna wrote:
> > > In any case, it is a lot easier to get x36 memory SIMMs than x33.
> > > High-end PC's greatly outnumbered Sun workstations of that vintage.
> > >
> > Do you mean that Sparcs typically use x33 SIMMs, while PC servers
> > typically x36? That's an interesting information on its own. Can x36
> > SIMMs be used in Sparcs?
> 
> I think, Suns don't use 33bit in general, i didn't try this, but i think, the
> SparcStation ELC/SLC needs 33 bits, other machines may need 36 bits. Alphas

I'm pretty sure the IPX needed 33 bits as well.

> sometimes need 33 bits (AlphaStation 200?), sometimes 36 bits (Multia?
> AXPpci33?)

LCA based machines need 36 bits, so Multia/AXPpci33. The service docs for
the AS200 say

<quote>
    * The system requires 72-pin parity SIMMs that have an access time of 70
ns (nanoseconds)
</quote>

36 bits definitely runs in AS200, that is what I have in one we have at
work.

> 33 bits are hard to get. 36 bits are easier to get.
> 36 bits run nearly everywhere, except some rare machines needing 40 bits.
> I'm using the standard 36 bit modules in Alpha, Sparc, IBM RS/6k, SGI and lots
> more here.

Yup, same experience here for Alpha.

-- 
|   / o / /_  _   		
|/|/ / / /(  (_)  Bulte		wilko@FreeBSD.org