I have HP ProBook 6475b laptop with AMD Radeon HD 7420G graphics card. 4GB RAM and Windows 7 Enterprise 32 bit OS. I see that graphics card is using about 800mb RAM. In windows resource monitor I see that 1828mb is hardware reserved and OS is using only 2,21gb RAM. In theory 32 bit windows is able to use around 3GB. So the question is using RAM from those 3GB that OS is able to use or from that one extra gb, that OS is nor able to use?