Can i use GTS 450 on my pc?

my pc has a nVidia GeForce 7300 GSO graphics card installed it says tht its 512MB DDR2... theres a pci express 2.0 slot. E4500 [2.20GHz] Core 2 duo processor.450W power supply.on board i have 2gb DDR2 ram.can i upgrade to NVIDIA GeForce GTS 450 {1gb DDR5}.will this DDR5 memory card be supported on my motherboard??