Originally Posted by jph1589
I still don't believe I've read anything that explains why my Vista Home Premium 32bit shows 2814MB available to vista (see my picture posting above). I have 4GB installed and my video card is only 320MB. So taking the worst case explanation that I've read in this thread, that means I should see somewhere around 3100MB available for use in Vista.
One of the articles posted leads me to believe that Vista would display 4096MB minus 320MB Minus other devices address spaces.
Another article posted leads me to believe that it would start that calculation at 3500MB not 4096MB.
I'm not trying to be a smart ass here but with all the experts we have here, it would seem that one of them would know the exact formula for arriving at the number that is displayed by Vista in system properties as the total Ram it has access to.
There sure are enough people who run around screaming about you need 4GB in vista. "OMG we all need 4GB". Where are all those people now to explain why the hell vista can't see it once we install it?
There is no "exact" formula, as it depends on the devices you have installed. As mentioned previously, this is because of Memory Mapped IO (MMIO). This is so that there can be one address space that a program can write to, and the address determines where the data gets sent.
I have taken a few Computer Architecture classes, so I know about this stuff. Basically every card and device in your computer will take up some of the address space, but I don't know exactly how every possible device works or how much address space it needs, so it is hard to determine the exact amount of RAM any one person will see in a 32-bit OS.
Basically more devices and add-on cards = less usable RAM in a 32-bit OS. If you just upgrade to 64-bit, your problems will be solved. It's only like $10 to send in for the 64-bit disk anyway (or free for Linux :-P).