Ok, sorry I misred you I though you had shove a gtx 480 into your brand new rig… sorry.
You can create a desktop shortcut and add the --disable-opencl option to the lauch options
PS : not so old but nevertheless driver update on these quadro linup seems to be less frequent, maybe the support for opencl is not so streamlined ? I’d be ready inclined to think that a more common GPU would eliminate some compatibility issues.
On the cheap side, 1650 would be an upgrade not requiering any 12v GPU connector where some other more expensive upgrade path would provide a more sensible amount of video memory to boost DT (depending the size of the files you open in it)