optiplex 5040

Hello , New here . I have a dell OptiPlex 5040 ; I want to transfer it into a larger tower to upgrade the GPU . My question is , can I give my MOBO too much power ? I have a 650W PSU I want to put on it . Im upgrading the case to fit the GPU which is a GTX750TI-2GD5 . Any and all help with this...