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is F@H single or double precision?

Posted: Mon Apr 27, 2009 9:06 am
by alpha754293
is F@H single or double precision?

Re: is F@H single or double precision?

Posted: Mon Apr 27, 2009 9:38 am
by jaak ennuste
I have a wild guess -- single

Jaak

Re: is F@H single or double precision?

Posted: Mon Apr 27, 2009 10:24 am
by ^w^ing
I think all the fah cores are single precision, except for the double gromacs cores (79,7b,7c), those are double precision.

Re: is F@H single or double precision?

Posted: Mon Apr 27, 2009 11:41 am
by toTOW
Here is a list of all cores that have ever been used in FAH with a brief description : http://fahwiki.net/index.php/Cores

Re: is F@H single or double precision?

Posted: Mon Apr 27, 2009 1:01 pm
by metal03326
I guess the GPU cores are single, because they run on HD 2x00, which do not have double precision.

Re: is F@H single or double precision?

Posted: Mon Apr 27, 2009 3:51 pm
by John Naylor
All cores are single precision except the three DGromacs cores which are double precision, as said by ^w^ing.

Re: is F@H single or double precision?

Posted: Mon Apr 27, 2009 5:53 pm
by ^w^ing
John Naylor wrote:All cores are single precision except the three DGromacs cores which are double precision, as said by ^w^ing.
woohoo \o/ :lol:

Re: is F@H single or double precision?

Posted: Mon Apr 27, 2009 8:12 pm
by 7im
metal03326 wrote:I guess the GPU cores are single, because they run on HD 2x00, which do not have double precision.
There's someone who know's GPUs. ;) Here's another bit of trivia for you to tuck away...
mhouston wrote:It's all currently single precision. All 800 on the 48XX SPs can support single precision floating point, leading to a 2.5X increase in peak performance. Double precision on the 48XX is also 2.5X the performance of the 38XX.
VijayPande wrote:With a lot of effort, one can rewrite code that depends on double precision to run in single. It's rare that the whole code requires double -- usually there's just a few precision sensitive parts. By treating these parts carefully (e.g. reordering the numerics to avoid things like adding big numbers to small numbers, etc.) single precision can always work, but with a lot of effort in some cases.

We've already done that effort in GPU1, so the GPU2 code benefits from this today.

Re: is F@H single or double precision?

Posted: Tue May 12, 2009 4:30 pm
by alpha754293
Good to know. Thanks guys. :)

Re: is F@H single or double precision?

Posted: Sun May 17, 2009 4:30 pm
by ColonelCain
alpha754293 wrote:Good to know. Thanks guys. :)
Indeed. :D Quite.