When I first installed my Quadro 4000, I needed to add these lines to the debug tab:
LsManager.3.NumGPUs = 1
LsManager.3.GPUMapping = 0
LsManager.3.GPUMappingEnable = 1
Before you login, go into the Davinci preferences (command + , ) and paste the code into the debug tab.
Josh Petok
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