[Beowulf] Slection from processor choices; Requesting Giudence

[Mark Hahn]

> GigE is not perfect. My point is that for many applications
> it can work well.

for many apps of certain job sizes...

> desktop (32 bit PCI) cards. I managed to get 14.6 HPL GFLOPS
> and 4.35 GROMACS GFLOPS out of 8 nodes consisting of hardware
...
> As a point of reference, a quad opteron 270 (2GHz) reported
> 4.31 GROMACS GFLOPS.

that's perplexing to me, since the first cluster has semp/2500's,
right?  that's a 1.75 GHz K8 core with 128K L2 and 64b memory
interface.  versus the same number of 2.0 GHz, 1M cores each with
4x 128b memory.  I really wouldn't expect them to be that close - 
any speculation on why GROMACS runs so poorly on the much better
SMP machine?