Ram compatible with my Computer?
 

This is my computer: HP Pavilion a320n Specs - DealTime

Says I have 512mb of Ram but really 448 <_<

This is what Crucial.com says what I need: here

This is what I plan to buy two of these (I'm cheap): K-Byte - 512MB PC3200 DDR DIMM Memory - 512MBPC3200

I never upgraded my computer.

So what I'm planning to buy compatible with my Computer?

You have 448 MB because the graphics chip on your motherboard is using 64 MB.

Yup, you can always buy DDR memory over specification. I would suggest buying from newegg.com though, if you're gonna do it online. It's cheaper, ships fast, and the customer service is top notch.