GTX 280 for computation + ATI Radeon HD 2400 PRO for display? arrange of computer resources

Hi, I wonder if I can use GTX 280 for general purpose computing only and use an old ATI graphic card for display. I just want to reserve more computation resources (SM, memory and register, etc.) for computation. How can I tell my motherboard to do that? Thanks.

Just install your ATI in the first PCIE slot…