Need help selecting RAM and Video card

I'm not totally new to computers, but for the past ten years I've just been using laptops. The last desktop I had was from about 2004 and I did some customization and upgrades to it but the world has changed in the meantime.

I recently acquired a Dell Inspiron 3668. It's a fine multimedia desktop but I'd like to upgrade the memory and add a video card. Dell's website isn't very good for this particular model, and when I enter the service tag (HJDKQJ2) I get very little info. Can somebody tell me how I can go about adding 8GB of RAM and a decent (nothing too crazy) video card?

Thanks in advance!

Submitted December 31, 2017 at 08:35PM by s1726354 http://ift.tt/2lztWEb