I posted the following on collatz message boards, reposting here in case one of you have an idea.

I have 2 boinc clients running on the same machine. One client ignores gtx 690 gpu 0 and the other ignores gpu 1, to solve an issues with getting collatz to run on both engines.

One of the clients insist on running solo_collatz_4.07_windows_intelx86__cuda50.exe and the other runs solo_collatz_4.07_windows_x86_64__cuda50.exe. I assume the x86_64 is what should be running. Neither has app_info.xml, both have app_config.xml (which are identical).

Both clients start up with log message "Starting BOINC client version 7.2.33 for windows_x86_64".

I have reset, detached/attached, detached, removed any boinc programdata file that referenced collatz in its name, reattached. Always the same result the one client runs the 32 bit app. I cannot figure out why. Ideas?