Your mainboard has the capability of using integrated graphics. That is why "hardware reserved" is showing up. It's not actually being used all of the time, and it can be used by programs if they need it.
In other words, on the board you have this is normal behavior.
thanks for all the replies
I am running an i5 750 and a 460 gtx on that board my understanding is the integrated graphics would not be used? I have written a program that shows only 2gb of usable ram, also this is a new thing and has only just happened up until a few days ago I had 4GB useable.
I would really like to know what the issue is. I can reinstall windows but what if this happens again? I dont want to be reinstalling windows every few months!