Added 4GB RAM to 2GB originally, System says only 3.25 GB RAM. How is this possible?
Answers:
Windows XP and Vista are 32-bit operating systems (unless you are running the 64 version, but I doubt you are). Both of these systems use 32 bits of memory to label and access locations in memory. Using 32 bits for this creates a theoretical limit of about 4GB of memory. However, some of the limits in the system, and memory used for other things, limits this even more.
Pretty much, you have more physical memory in your computer than your operating system is able to address/use.
Vista (and maybe XP) only recognizes up to 3.25 or so.
hes right!
check your motherboard's stats, it may not be able to handle all the RAM..
also, if the 2 types of RAM aren't exactly the same type, the motherboard will use the biggest size one and ignore the old RAM. the newer one is probably faster than the older (is the old memory turbo and/or dual channel?)
Did you check to see if your motherboard would actually recognize 6 GB? And the previous answer was correct. Try the Belarc Advisor to see if your mobo will actually accept and use 6 GB.
www.belarc.com
I can't get my page to come up, so I'm not able to actually give you the link to follow.
To address 4GB of memory you need 32 bits of address bus. (Assuming individual bytes are addressable.) This gives us a problem - the same problem that IBM faced when designing the original PC. You tend to want to have more than just memory in a computer - you need things like graphics cards and hard disks to be accessible to the computer in order for it to be able to use them. So just as the original PC had to carve up the 8086's 1MB addressing range into memory (640K) and 'other' (384K), the same problem exists today if you want to fit memory and devices into a 32-bit address range: not all of the available 4GB of address space can be given over to memory.
For a long time this wasn't a problem, because there was a whole 4GB of address space, so devices typically lurk up in the top 1GB of physical address space, leaving the bottom 3GB for memory. And 3GB should be enough for anyone, right?
So what actually happens if you go out and buy 4GB of memory for your PC? Well, it's just like the DOS days - there's a hole in your memory map for the IO. (Now it's only 25% of the total address space, but it's still a big hole.) So the bottom 3GB of your memory will be available, but there's an issue with that last 1GB.
yes the system uses some ram at srartup
The answers post by the user, for information only, RunQA.com does not guarantee the right.
More Questions and Answers ...