I just ran NVidia experience and it correctly identifies my video card as a GeForce GTX 260, shows a circle with slash through it for not compatible for games optimization, and has an error "sorry, GeForce experience cannot optimize games on this PC".
My CPU (intel Q9550 quad core), 8GB ram, and OS are all listed as supported.
When I go to the drivers tab, it says "Your GeForce driver is up to date", with 341.81 version installed. Checking further, it says game optimizations are available only for GeForce 400 series GPU or higher. Even clicking on "beta" driver notifications doesn't get me any driver options past 341.81.