It depends if you are thinking of returning more credits or of actually doing more work.

If you are thinking of producing more work there seems to be a much better performance (about 30 %) in 64-bit mode for HCC WUs. I observed it under Ubuntu (Linux) but I think that it should be the same with 64-bit Windows, the reason being that, at least for some of the 64-bit processors, the processor is much more efficient on integer computation than in 32-bit mode. Since there is no noticeable difference of performance between 64 and 32 modes for floating point computations WUs which are running essentially in floating point mode (all except HCC) do not show a noticeable difference.

However, if you are thinking of getting more credits it is no longer as beautiful. For various reasons which are difficult to overcome work done under Linux systems is often less credited than it would be under Windows, therefore the benefit is mitigated for HCC in 64-bit mode, and it would probably be negative in 32-bit mode as well as for all other WUs in both modes.


Even if it were running 100 times faster that would not matter because the Boinc client is only organizing and managing the work and uses very little CPU power. The hard work is done by the science applications, and their performance depends on the type of computation they are doing and how efficiently they have been designed and coded (see above).

And, as said by Didactylos, everything I have written here is based on observation (much, but still...) and reasoning, but not on inside knowledge of the science application or the systems. And not on exhaustive testing as well since it is not possible to run the same WU in different environments under normal operating conditions.

Edit: Clearly said, "based on much observation" means statistical observation on lots of results produced under Ubuntu 64-bit and XP 32-bit.

Cheers. Jean.

If you feel ready for the move, just do it, if I am still allowed to say.
When they get HCC WUs they will love it, and for the other projects they should do at least as well as with W2K, I think.

Good luck for the move. Jean.

Just two quick comments (I am gnawing an other big bone right now ):
1. You would have to add the clock frequency to the OS/processor combo...
2. I have seen this kind of effort started on the site of a very big team with lots of members more excited with getting credits than with what they are computing. And even there it sinked into oblivion after a few posts: too many particular cases make any consolidation/organization effort not sustainable.

Cheers. Jean.

Hello Jean;
I don't know if you were talking about us at Xs but even if not I'd like to comment on it.
You get many different kinds of people on the teams.
The purists who don't care about points at all but are just there for the work. Those are a minority from what I've seen. Good folks but overall in the minority.
Then you see the people whose first motivation is the work but also like the thrill of competition. Those compose the majority and even in that group there are differences in the amount that an individual is "into" the competitions.
I'd toss myself into that group.
I'm here for the work but I do enjoy competing but not as an end all.
In the last 2 years I've probably put over 5 million points on other members and other teams names in the spirit of good will or in the case of one team here to say that I was touched by the loss of a child.
Then last you do have a small group that would run an app that counted tiddly-winks if it gave points.
These programs I consider worthless but it is not my place in life to tell others what to do. I can only suggest and do my sales pitch for WCG and hope some listen.

Now as to what windows OS score better than others it seems from what I've seen that Vista Ultimate 64 and win2k8 64 score the best.

I run neither at this time.
Vista is persona non grata in my home.
Too much work to make it into what it should have been when released.
I run winxp 32 on two machines, win2K3 server on the two clovers and winXP 64 on my harpertown machine.
I'll have a Nehalem machine up and running tomorrow but unfortunately I can't put it on WCG until the NDA lifts on November 16 as Boinc grabs numbers on the processors efficiency and lists them here even when your machines are "hidden":
http://boincstats.com/stats/host_cpu_stats.php?pr=wcg&st=0
If you know of a way to get around that I'd be interested in hearing it as this machine is a beast in terms of computational power but I did agree not to post numbers or pictures until the NDA lifts.
Thanks for reading.