7.6.33 w/o virtualbox, tried both, not as service, run SETI
win 7-64b home, asus nv56 full hd, i7-3610QM, 8GB, intel HD 4000 + nvidia GT 650M (2GB)
since current updates, win crashes when starting boinc, saying something like
"nvidia gpu is not a removeable device, cannot unlink"
a ~200Hz sound appears, image is frozen, system unresponsive
can only reboot with 10s powerswitch.
Before, boinc ran correctly when system was idle.
What changed ?

Reading around on the internet, this problem is caused by the Nvidia drivers. Try to install a lower previous version, doing a clean install of them. That's apparently an option in the installer itself, you may have to look around in the options a bit.

Also see https://forums.geforce.com/default/topic/913286/nvidia-gtx970-seen-as-a-removable-device/?offset=6 on what other users of Nvidia GPUs found about it, including a hack to hide the message.

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