[Wien] 2 XEON 5355 or 4 XEON 5150?

[Alexander Shaposhnikov]

Hello,
the best choice would be to stay away from Intel Quad-core Xeons if possible, 
for now at least.
The memory subsystem performance on current gen 5000X/P platform is very low.

To be more specific, 4-channel FB-DIMM memory on this platform is 
substantially slower than 2-channel DDR2 memory on desktop. 

As a result, SMP scaling with Quad core CPUs is simply inadequate.
Dual-core Xeons will scale better, of course, but there is better alternative.

To tell the truth, for small budget cluster the best bang for the buck would 
be Intel desktop Quad-cores, namely Q6600 (2400MHz, 300$), overclocked.
My testing shows that single  Q6600  G0 stepping, overclocked to 3.6 GHz 
(which they can easily hit for 24/7 full load operation ) is as fast as two 
Xeons X5355. Cost is 2x-3x less.

Best Regards

On Friday 19 October 2007 22:44, Q Z wrote:
> Dear All,
>     We plan to buy a new computer for Wien2k calcualtion. There are two
> choices, one is use 2 quad core CPU (Intel XEON 5355),the other is use 4
> dual core CPU (XEON 5150). Which one is better for parallel calculation?
> Somebody told me that the speed is slow down  if runing a job in parallel
> using the 8 cores of  2 XEON 5355. Is it right?  Thanks in advance.
>
> Best regards,
>
> ZM