Yes. 64-bit in the GPU specification is the GPU memory bus width. It's not a requirement for CPU register (it's not stating a requirement of a 64-bit CPU). So a quadro 285/290 video card w 64 bit memory bus can work with a 32 bit cpu.
I have read previous posts here about this topic but would still like advice in case I wreck my mother board!. Basically its an old Dell 32 bit Optiplex 755 SFF that I use for accounts and documents, its a stand-alone that never goes online. Trouble is now as my eyes are getting older the detail on the monitor is not so sharp unlike my other PC which is also a Dell but a 64bit and has a decent graphics card fitted.I have two spare graphics cards which I believe are 64 bit, one a NVIDIA Quadro NVS 285. the other a nvidia quadro nvs 290. So the question is being 64 bit will they work in a 32 bit system. ?
Dell 32 bit Optiplex 755 SFF Graphics Card Upgrade