I've found a problem similar to the one found on this thread:
http://boinc.berkeley.edu/dev/forum_thread.php?id=8647

I run BOINC on 2 PC, the 1st with ATI 5770, the 2nd with a 7790, both win7 64-bit + BOINC 7.0.28, and catalyst 13.9
The 5770 is seem by BOINC as:
06/02/2014 10:55:58 | | ATI GPU 0: Juniper (CAL version 1.4.1848, 512MB, 479MB available, 2720 GFLOPS peak)
The 7790 is seem by BOINC as:
27/01/2014 18:54:21 | | OpenCL: ATI GPU 0: Bonaire (driver version 1268.1 (VM), device version OpenCL 1.2 AMD-APP (1268.1), 1024MB, 1024MB available)

so on the 5770 can run projects both OpenCL and CAL based. But on the 7790 all client CAL based show this BOINC log message:
09/02/2014 22:18:10 | | App version needs CAL but GPU doesn't support it

I've reported this problem also here:
http://www.primegrid.com/forum_thread.php?id=5504&nowrap=true#73346

any idea to load CAL also on 7790 ?

AMD has stopped support for CAL in their drivers. Also not sure if they still support it hardware wise on their newer models of GPU. Anyway, you're not alone, here at Seti (I'm pointing to post 1460154 and further in this thread), there's other people with Bonaire style GPUs which don't do CAL.

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