[rescue] Re: Wanted - Dual (or quad) PPro motherboard

[Gavin Hubbard]

>> I personally run a Unisys Aquanta HS/6 (basically an OEM'd ALR Revolution
>6x6) with six PII Overdrive CPUs and it hasn't missed a beat in the last two
>years. I consider it a 6-way mini-Xeon system. In terms of performance, the
>OD CPUs are a big step up from the 200MHz/512K chips I used to run.
>
>How big a step up?  I thought I heard that the OD chips were only a marginal
>improvement.  If they're that good, I might look for a pair to stick in my
>peasea.  Dunno if I want to replace the 1024K chips in my IBM yet.

The gain is fairly substantial for most applications, but the amount of
speed-up depends on what sort of code you are running - for example the PII
OD supports MMX while the PPro does not. The 200/1MB chips seem to perform
better with certain memory intensive apps e.g. large databases but you need
to tune your system to get the best performance. If you're not careful and
get data sloshing between the caches on the relatively narrow (shared
66MHz) system bus, the performance drops like a stone.

But then again if you were concerned about raw performance, you probably
wouldn't still be using your PPro system :-)

>>
>> I have also heard of people successfully running four PII Overdrives in
>quad CPU boards.
>>
>> Incidentally, I'm still keeping space set aside in my zoo for a system
>running multiple 200MHz/1MB Pentium Pro chips. I used to lust after them
>really badly when I was younger.
>
>Like a Netfinity 7000 (8651-RH0)?  Quad PPro200/1024 w/ up to 4GB RAM, 12x
>hot swap SCA bays
>
>I saw a Xenon-based Compaq go for $reasonable on epay a few weeks back.  4x
>2MB chips w/ 1.5GB RAM...

The Netfinity should work OK with the ODs. However a Xeon-II system will
easily give superior performance (everything else being equal). The older
Xeon chips are so cheap these days that you can't go past them for
home-brewing a large SMP system. However unless you can get a fully
configured system, I would stay away from systems with more than four Xeon
CPUs. as certain parts e.g. cache coherency filters, are extremely
difficult to find.

Incidentally, you can also get convertors that allow you to mount first
generation Celeron systems in PPro boards. IIRC you can get them from
www.powerleap.com - they only downside is that SMP is only supported up to
533MHz (Intel disabled it after that) and SMP is limited to dual
processors. However if you have an old dual processor board I understand it
is a worthwhile upgrade.

Regards,

Gavin


P.S. Joshua I will try and build a case for the PPro's impact in a couple
of hours :-)