After reading your post, I did go through the Product specifications of your product and found that you have 500 GB 5400 rpm SATA and 2 GB 1600 MHz DDR3 installed on the PC.
And you can expand memory up to 8 GB and hard drive up to 1 TB. Refer to: c03939664.pdf (hp.com) 2 Chapter 1 Product description
Hope this helps! Keep me posted for further assistance.
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