Given the reference to Dropbox, I did some reading on this, and do not feel it is related.
While I use Google Drive, I do not use it for any storage locations as those reporting issues with Dropbox do - I mostly use Drive to sync documentation, my .NET source code, CAD-related support/settings, etc. between work and home (in the event my terminal server is unavailable for sown reason). Nothing in my CAD setup is loaded from Drive - these are just backups.
That said, there is a literal difference in CAD behavior when Drive's service(s) are running, and when they're not - I'm at a loss on any correlation, besides the gigabit network, which has never been an issue before.