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Where did the other .8 GB of RAM go?

I am using Windows 7 32-bit on my laptop, and I have 4gb of physical RAM.

In my system properties, it says that 2.99GB are usable. Does this mean the other 1GB are basically useless or are they being used for other things that do contribute to keeping the computer running smooth?

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marked as duplicate by Sathya, Diago Dec 28 '09 at 7:45

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Correct. They are basically useless under a 32-bit operating system. Welcome to the x86 legacy that your devices are mapped to the upper end of your 4GB address space and mask it from its intended use.

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usually it's around 3.5 GB, but you probably have to allow for shared video memory if the laptop doesn't have a dedicated video adapter. then that figure is quite normal. –  Molly7244 Dec 28 '09 at 1:52
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The RAM is not useable, because that part of the 32bit address space (i.e. 4GB overall) is reserved for memory-mapped IO to various hardware devices, most prominently the video card.

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