A friend of mine recently posted on Twitter an image like the one above. Very logically he posed this question… How does 3.65 + 0.35 = 3.75? Is this some strange new cult of Apple mathematics? There appeared to be missing 256MB of RAM. Concerned for my friend’s memory loss and a bit puzzled myself, I opened my Activity Monitor. You can see, I had exactly same result. Being the Mac geek that I am, I didn’t panic. I figured there had to be a logical explanation. Maybe this was like hard drives where they say 1 TB on the box, but in reality you get less. That happens because when marketing the hard drive they base the numbers on 1GB equaling 1,000 MB instead of the actual 1024MB that it should. In the case of my RAM that wasn’t it. So what gives?
A quick Google search revealed the logical answer. It’s something I should have realized immediately but didn’t. See, I have a newer 15″ Macbook Pro with an integrated NVIDIA 9400M GPU and it uses… You guessed it. 256MB of shared RAM.