DEC Alpha 566 vs. 600 MHz

 Dear CCL-ers,
 We are considering purchase of a workstation based on DEC Alpha processor.
 There is a substantial price difference between 566 MHz and 600 MHz:
 7000 $ vs. 8200 $ which is about 17%, while the increase of
 "nominal" processor speed is 6%.
 My question is: does anyone know from his own experience what is the actual
 speed difference between these two procesors in typical theoretical
 chemistry or solid state physics calculations. I guess that it is larger
 than simply 6%. In other words I wonder whether it is reasonable to pay
 17% more for faster machine - is the gain worth the money?
 I would be grateful for any suggestions,
             Andrzej Eilmes
 ----------------------------------------------------------------
   Dr Andrzej Eilmes                   eilmes -8 at 8- trurl.ch.uj.edu.pl
   Faculty of Chemistry, Jagiellonian University, Cracow, Poland
   Phone: (48-12) 6336377 ext. 213          Fax: (48-12) 6340515
 ----------------------------------------------------------------