Only sharing a few bits of what's seen my side: My quad depending on science mix does very well under Ubuntu... 300-400 credit more per day for what I'm doing now [Ubuntu 64 bit v W7-64]. DDDT2 so far is the wildcat in the cage. Ranges from 10.6 to 28.5 per hour depending on whom you meet in the quorum. WCGDAWS computes a mean per hour for this system of 18.8 for the current rain, which compares to 21.8/hour for the whole WCG compendium of sciences, past 4 days. That drawn on W7-64... was ~16/hour, so guess what... equal or more science and points to measure contribution ;>)

Summary: My choice for a purely dedicated cruncher is Linux and for easiest operation, Ubuntu. Most of the time the GUI is killed, and that saves quite a bit of CPU cycles, to only run in Terminal.

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P.S. BUT, I boot into W7-64 to do CEP2. They run on my hardware more efficient, up to 99.2%, where Linux I never see above 97% these days... mostly 95-96%. There's no discernible processing speed [CPU time] differential for this science between Linux and W7-64]. Observations can differ, too many system variables on HW/SW fronts. Looking forward to try Linux 3.0 under the next Ubuntu release, Oneric Ocelot, with promised fixes to spped and power management.

Differential a not grand, much depending on what candy interface you use, it's a drama. KDE does the vacuum-ie sound... 25% (taking nearly a whole core in 24 hours). GNOME Classic, Unity about 2-3%, on me quad. Then there is the real gloss-up [aero-like] taking it's toll and keeping Firefox loaded... bad idea. Caught it recently having taken over 1Gb of VM and 640MB RAM... and that's the 5.0.

Killing the interface we discussed with kateiacy IIRC. Different ways, I do a "sudo service gdm stop" to truly end the GUI. Come to think, would there be one for KDE? It's seems to nearly irremovable stuck such luminary ''features'' as tracker-store running and running and running (probably it's continuously indexing the BOINC data dir :( )

Remote monitoring with BOINCStats, but boinccmd in terminal allows for doing it too. :O)

Think we got way off topic here... apologies.

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Hi Roberto,
if you have 2500 USD to invest I think that you can build a strong config for your new rig to get the maximum results crunching on WCG projects and others.

Once energy could be a concern, I would like to suggest the same that Bearcat: consider build a dual socket motherboard (ex. dual xeon) which for sure will fit well in your planned budget, and if builted with care and with right components could provide great overclocks and results.

One machine with dual socket can start simple, and evolve according your experience, and will be more easy to manage than many machines and will for sure consuming less energy at end of day (despite of could produce a little bit less results if compared with many machines using i7 processors configs like ones mentioned in some posts above). Good luck in your decisons.

Can vouch for super micro using dual westmere running ubuntu 64/Win7 64. 2X12 Magny-Cours's would be nice to crunch with.

Walk THEN run? Oh, my! What rock have you been hiding under for the past thirty years? That's not the way it's done nowadays.

What you do now is to locate an 'expert.' Your expert needs to have some sort of 'qualification' - preferably unrelated to the matter in question, and having been obtained by virtue of your expert's membership of some variety of politically-targeted victim group. This allows anyone disputing your expert's opinion to be dismissed as a something-ist reactionary.

The only essential qualifications that your expert needs is the ability to translate your mangled jargon into a more impressive form and to agree with you. By arbitrarily redefining night as day, wet as dry and hot as cold, your expert will be able to convince you and prove to your superiors that your scheme to import dehydrated water from the moon will be profitable.

Some of the better experts will be able to patent it, arrange a government grant and even write a thesis on the matter and become an even-more-expert expert into the bargain.