32bit OS not recognising RAM greater than 4GB??

gamerman4 said:
The Address Space is being used elsewhere. The RAM is not being addressed, therefore not accessible.
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By the Operating System. It can still be accessed by the motherboard. You said it in your article.

If it is a 64bit memory controller

"When something is read from your memory, your computer finds what it needs in the addressing space, it is kindof like an IP address, it represents something in the virtual world. The addressing space is limited by the bit depth of your memory controller, which in most modern systems is actually better than 32-bit, (128 bit i think, please correct me if I'm wrong). The limitation here goes from your memory controller to your OS. If the motherboard memory controller were 32-bit, a 64-bit OS would be limited as well. A 32-bit OS can only register a 32-bit address space which it uses to address places in your RAM and also addresses your system components. According to your OS, RAM is just another component to be addressed and it just addresses everything in the same pool which is why 4GB of RAM is limited by the devices in your computer."
 
You think we could get a sticky on this so everytime someone comes in here we don't have to waste a new post on it. Well then if they did a quick Google search that woudl fix the problem too.
 
ComputerGuru64x2 said:
By the Operating System. It can still be accessed by the motherboard. You said it in your article.

If it is a 64bit memory controller

"When something is read from your memory, your computer finds what it needs in the addressing space, it is kindof like an IP address, it represents something in the virtual world. The addressing space is limited by the bit depth of your memory controller, which in most modern systems is actually better than 32-bit, (128 bit i think, please correct me if I'm wrong). The limitation here goes from your memory controller to your OS. If the motherboard memory controller were 32-bit, a 64-bit OS would be limited as well. A 32-bit OS can only register a 32-bit address space which it uses to address places in your RAM and also addresses your system components. According to your OS, RAM is just another component to be addressed and it just addresses everything in the same pool which is why 4GB of RAM is limited by the devices in your computer."
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Which is why a 64-bit OS would be able to use all 4GB of RAM, because a motherboard memory controller is often above 64-bits. It is irrelevant whether a motherboard can access RAM, why would a motherboard need your RAM? Software doesn't directly access RAM through the memory controller, it accesses it through your OS. Therefore the extra RAM is useless to a 32-bit OS.
 
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If you hadn't noticed, I wrote that article on this issue, I did a lot of research. If you have proof that software can bypass the OS and access un-addressed RAM, then please tell me how that is possible and I'll add that to my article.
 
Your missing my point because im saying that is it being used, just not by the operating system. The .75 has no value to me or him while were on the computer.
 
The solution is easy, open up your boot.ini file in the root of your system drive. At the end of the line for your XP installation, add "/PAE" without the quotes. This enabled the physical address extensions which will allow you to use up to 4GB of memory (the upper limit in XP Pro).
 
ComputerGuru64x2 said:
Your missing my point because im saying that is it being used, just not by the operating system. The .75 has no value to me or him while were on the computer.
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What is using it? Motherboards don't use it. The OS can't address it. Software can't use it.

It is "installed". It is able to be "seen". But utilized in any way to benefit the performance of your system, no. Unless you have another definition of used.
 
Our definition of wasted must be two different things. We cannot put exactly 3.25Gb of memory to max the amount of memory in XP. We instead use DDR2 (2x2Gb) sticks to max out the amount of RAM. How can it be wasted if it isn't being used because it isn't accessible. I don't understand what wasted means; when you can access it?
 
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ComputerGuru64x2 said:
Our definition of wasted must be two different things. We cannot put exactly 3.25Gb of memory to max the amount of memory in XP. We instead use DDR2 (2x2Gb) sticks to max out the amount of RAM. How can it be wasted if it isn't being used because it isn't accessible. I don't understand what wasted means; when you can access it?
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I didn't say the stick is wasted, I said the unaddressed RAM is wasted. the .25GB used by that last piece is still useful.

Also, you could technically put 3.25GB of RAM in a machine, it just isn't practical.
 
If you have a box that can hold 4lbs of rice but you can only buy 5lb bags of rice. that last pound is wasted on your box. because it can't hold the rice. If you ship that 4lb box to your friend, the 1lb that you couldn't ship (and he can't access) is absolutely useless.
 
I say we stop arguing and agree that .75gb has no value but it is still physically there. It cannot be applied in a 32bit OS. But it isn't wasted because it does get mapped? Agreed?
 
It might or might not be physically addressable (it depends). But when the memory manager in Windows denies access to it, it is wasted. The memory cells wont ever be used to store data. It is that simple.
 
Agreed. I can't wait till everyone is using 64-bit OS's because this will not become an issue until we reach the 64bit address space limit (a looooooong time from now)
 
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