Looking at the information you provided (HP Pavilion - AY587AA-ABA MS225), this appears to be an All-in-One computer. Most All-in-One computers that I have dealt with in the past were a really big pain to change out components. I have even seen some where the parts are soldered onto the motherboard. The graphics card is actually Integrated graphics and the motherboard does not appear to have a slot to put a dedicated graphics card. The RAM is already at the motherboard maximum of 4GB. The CPU looks like it is the only thing you can upgrade on this PC. I am unable to find specific information on what you can upgrade to, from your current CPU. If someone here is unable to help, you may want to send an email to HP asking them what options are available for your PC.