Opteron DP question

i remember with my old PIII dual CPUs i had to buy them at the same time
so they would work in a DP system, do Opterons have tht same issue...?
ie could i buy a single Opti CPU for a DP board and buy the second CPU
months down the track...?

Paul Gunson wrote:
i remember with my old PIII dual CPUs i had to buy them at the same time
so they would work in a DP system, do Opterons have tht same issue...?
ie could i buy a single Opti CPU for a DP board and buy the second CPU
months down the track...?


I helped someone build a Opty dualie based on a Tyan S2885.
He started off with one Opty 240, then added a second one
three months later. He just walked into a store, asked
for an Opty 240, payed for it and walked out. He plugged
it in and it worked - maybe he just got lucky, but he made
to effort to match steppings or anything like that.

You should check out the forums at 2cpu.com and consider
asking your question there.

"Paul Gunson" wrote in message
...
i remember with my old PIII dual CPUs i had to buy them at the same time
so they would work in a DP system, do Opterons have tht same issue...?
ie could i buy a single Opti CPU for a DP board and buy the second CPU
months down the track...?

Well, you would have to make sure you get the Opteron 2xx series of
processors, of course. As for whether you can buy an Opteron now and a
second one later, there's never any guarantees; it's always possible that
AMD might find some multiprocessor behaviour that it tweaks thus changing
the Opteron's behaviour between minor revisions, thus making them not
entirely compatible. However, that being said, word is that the Opterons are
some of the most outstandingly multiprocessor friendly chips out there,
mainly due to its Hypertransport interconnects.

With Hypertransport, processors have a much easier time maintaining cache
coherency since it is a point-to-point interface and not shared-bus. In
fact, there is word that Hypertransport will be upgraded to 1Ghz (from
800Mhz) in the not too distant future, but likely whatever processors are
out there right now will continue to communicate at their own speeds.

I suspect that HTT is so flexible that you might even be able to run
different speeds of Opteron in the same motherboard. But I doubt it would
ever be supported though.

Yousuf Khan

On Fri, 09 Jan 2004 10:32:43 +1300, Paul Gunson
wrote:
i remember with my old PIII dual CPUs i had to buy them at the same time
so they would work in a DP system, do Opterons have tht same issue...?

In a word, no. Actually the PIIIs really didn't have much of a
problem with that either, it was more a leftover piece of advice from
the Pentium and Pentium Pro days. Incompatibilities between
dual-processor PIII chips did exist, but they were pretty rare (I
don't know if it's still up, but Intel used to have a listing of which
PIII chips would work together and which wouldn't, most were fine but
there were a couple combos here and there that didn't work).

ie could i buy a single Opti CPU for a DP board and buy the second CPU
months down the track...?

Yup, shouldn't be a problem at all, as long as you get Opteron 2xx
processors each time. They should even work with different
frequencies, though I wouldn't test my luck on that one if I were you.

-------------
Tony Hill
hilla underscore 20 at yahoo dot ca

On Fri, 09 Jan 2004 00:51:31 +0000, Yousuf Khan wrote:

snip
I suspect that HTT is so flexible that you might even be able to run
different speeds of Opteron in the same motherboard. But I doubt it would
ever be supported though.

Actually, SMP with varying speed chips is even supported with the MP(X)
chipset, although I've never read about anyone crazy enough to try it.

With the original posters question, he should be fine with his plan. You
haven't had to match CPU steppings in a long, long time.

--
Most people have two reasons for doing anything -- a good reason, and
the real reason.