I have a Athlon 64 X2 Dual core processor 4800+ 2.50 GHZ with two 1 GB 240 pin DDR2 667 hertz. I tried to install a 2 GB chip and it failed to work do I need to install 2 (1) GB chips to get 4 GB of ram. I am running windows 7 and also do not know what video card as The computer is a recent gift to me from a friend. What would you recommend I do to improve its speed. I do a lot of digital photo work and use photoshop alot. Happy new year to everyone!