[Beowulf] Intel quad core nodes?

[Barnet Wagman]

> minor version changes in SSE, etc, and iirc the earliest Core2 chips had
> just 1066 MHz FSB, vs 1333 now.  you can probably come pretty close by
> populating just one node's dimms on a dual-socket AMD system.
Intel's non-xeon quad processors still have only 1066 MHz FSB (except 
for the very pricey QX6850).  This leads to a tricky trade-off.  I 
presume that contention can be reduced by (i) getting a processor with a 
1333 MHz FSB and (ii) building single (quad) processor nodes. But to get 
a 1333 FSB, you have to go to a 5000 series xeon.  These processors are 
considerably more expensive than non-xeons (at a similar clock speed).  
Furthermore, as far as I can tell, there are no single socket boards 
that support the 5000 series.  So the question is, which has less 
contention, a single quad processor system with 1066 FSB or a dual 
processor system with 1333 FSB?  My guess is the former, if all the 
cores are kept busy.  My app is embarassingly parallel, so it's likely 
they will be.

Of course I'd rather wait for AMD's quad but that's not an option (I 
doubt that they'll be readily available until next year).  So I'm 
leaning towards the low cost per node solution - one quad processor 
(probably a Q6600) per node.