[rescue] SGI, Origin 200, and speed?

[Joshua Boyd]

On Mon, Apr 26, 2004 at 04:07:07PM -0500, Micah R L wrote:
> Sometime in the past month we were talking about SGI speed and how a 
> 195MHz something was way slower than a 195MHz something-else ... I can't 
> find it in the archives (lordy, we put a lot of mail through here). 
> Anyone have a link?

The discussion was about Octanes versus Indigo2s.  Specifically, Octanes
are much faster than Indigo2s, even if both have a 195mhz CPU, and this
is due to the difference in memory bus between the two machines.
 
> I've been looking at an Origin 200s in the Austin area on eBay that I 
> might buy. Does the above mentioned discussion pertain to Origin 200s? 

Yes.  A single processor O200 @ 180 mhz should be soundly faster than an
Indigo2 at 195 mhz for any task complex enough not to fit completely in
L1 cache. 

> Should I know anything about them before I purchase one? I can get a 
> dual processor 225MHz one for 200$, but there's no shipping, and buying 
> a 195MHz one for 99$ + 60$ shipping from Andover doesn't seem to be that 
> much better. I also might try to bargain them down to their dual225MHz 
> unit + their single225MHz unit for 300$, local pickup, and then Craylink 
> em when I get another 225MHz proc in there. Good idea/bad idea? Price ok?

Upgrading from a single to a dual processor Origin200 is usually
considered a forklift upgrade.  Technically a motherboard swap should do
it.  I don't believe it is as simple as a CPU module swap.  It certainly
isn't a case of just popping in a second CPU the way PCs are.

I would go for the dual 225s personally.  Dual processor SGIs should be
a very invigorating experience.  From the Octanes on, I believe every
SGI memory bus is fast enough to keep up with at least two CPUs
completely (with the possible exception of dual R14ks in an Octane). 

If fast, if I could, I'd for the $300 deal you mention, even if I
couldn't cray link the two machines together.