Wednesday, May 23, 2007

4GB RAM in Windows

http://live.pirillo.com/ - Windows Vista 32 bit "supports" up to 4GB of memory, but is 4GB of memory enough to run Windows Vista? Sometimes it's more than enough.

If you're running a 32 bit system, 4GB is your technical upper limit. Of course, Windows may not report that you have all 4GB available! Addressof has a good article on why this happens:

Here is a little piece to the total 64-bit puzzle that no-one seems to be telling anyone about. In that 4GB of address space, your video card memory is partitioned. Meaning if you have a 256MB video card, 256MB is consumed in the 4GB of total addressable space that a 32-bit processor can utilize. Here's the problem; what if you have a video card that has 512MB, 640MB, 768MB? Yup, that will be mapped to the 4GB of addressable space. So if you had a 768MB NVidia 8800 card and 4GB of RAM, you'd lose 768MB of that 4GB of memory immediately to the device making it non-accessible "memory" for the OS. And it doesn't stop there, all of your other devices that need to be communicated with (you know, anything with a driver) consumes part of this address space. So in my current 4GB worth of RAM system, 1.25GB worth of addressable space is consumed by devices.

Under a 64 bit system you can use 4GB of memory and much more - up to 16 exbibytes! And if we know Windows, it will use all 16 exbibytes ;)

Is 4 GB of memory enough to run Windows Vista? Yes it is, according to Chris. What do you recommend?


No comments: