google translate french to english:
http://forum.boinc-af.org/index.php/topic,4132.0.html

Hello,
1_ I would like to run my GPU with BOINC and folding one after another on my HD4770 (in a few months to go for the HD5770 core v7 folding), but in the preferences of BOINC manager there is just "use gpu when the computer is used. No possibility of computed between 6am and 22h for example.

2_ Will there see this option in the next version of boinc (6.12.18).

3_ In addition, currently in single gpu, I wonder if he can just use a GPU that he has indicated, and then leave the other.

1 + 2: No, such an option isn't available now, nor will there be in 6.12
3: That is possible, using a cc_config.xml file and the <ignore_cuda_dev>0</ignore_cuda_dev>, or <ignore_ati_dev>0</ignore_ati_dev> options.

Example given, if you have two ATI GPUs and one Nvidia GPU, they'll be called devices ATI0 and ATI1 and Nvidia0. You want to omit using the second ATI GPU. Here's how, add the follow lines into your cc_config.xml file:

<cc_config>
<options>
<ignore_ati_dev>1</ignore_ati_dev>
</options>
</cc_config>

Save changes to cc_config.xml and then fully exit BOINC & restart it. Changes to GPU detection can only be done at BOINC start-up, they cannot be done while BOINC runs already. So Open BOINC Manager->Advanced view->File->Exit->Check "Stop running science applications on Manager exit?"->OK, then Windows Start button->(All) Programs->BOINC->BOINC Manager.

<ignore_cuda_dev>0</ignore_cuda_dev> will ignore CUDA device number 0 (first Nvidia chip or card).
<ignore_cuda_dev>1</ignore_cuda_dev> will ignore CUDA device number 1 (second card).
etc.

<ignore_ati_dev>0</ignore_ati_dev> will ignore ATI device 0 (first ATI chip or card).
<ignore_ati_dev>1</ignore_ati_dev> will ignore ATI device 1 (second ATI chip or card).
etc.

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