A:Answer http://support.hp.com/us-en/product/Compaq-Presario-SR5000-Desktop-PC-series/3733098/model/3740343/document/c01237548/
this gives you all of the information needed about your PC, Good luck!
(you will need DDR2 RAM not DDR3 and make sure it doesn't say ECC that RAM is used for servers and will not work for your computer, also make sure the Ram is compatible with your processor, by checking with the link above or in your PC settings>processor info)