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3GB RAM Limit 1
- Thread starter 200820
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- #4
I'm pretty sure it's 32-bit, is there a way to check this?
'Ver' at command prompt returns 'Microsoft Windows XP [Version 5.1.2600]'
Is there anyway at all that a 32bit system canrecognise 4GB RAM, I've seen a few articles about PAE (physical address extension) but not confident of how to implement it...
'Ver' at command prompt returns 'Microsoft Windows XP [Version 5.1.2600]'
Is there anyway at all that a 32bit system canrecognise 4GB RAM, I've seen a few articles about PAE (physical address extension) but not confident of how to implement it...
- Thread starter
- #6
PAE can only be taken advantage of if the software is written to take advantage of it. When you factor in all of your machine's memory, you won't get a performance boost.
"We can categorically state that we have not released man-eating badgers into the area" - Major Mike Shearer
"We can categorically state that we have not released man-eating badgers into the area" - Major Mike Shearer
Hey,
Windows XP 32 bit supports up to 4 GB. Windows takes this and splits it in half, using 2gb for apps, and 2gb for the kernel. If you add the /3g switch the boot.ini, then it uses 1gb for the kernel, and 3gb for apps.
Brendan Murtagh - HostMySite.com
Technical Support Representative
bmurtagh@hostmysite.com
Windows XP 32 bit supports up to 4 GB. Windows takes this and splits it in half, using 2gb for apps, and 2gb for the kernel. If you add the /3g switch the boot.ini, then it uses 1gb for the kernel, and 3gb for apps.
Brendan Murtagh - HostMySite.com
Technical Support Representative
bmurtagh@hostmysite.com
- Thread starter
- #9
Like others say: unless you have 64bit or are using CAD software, DON'T bother, it will not improve anything, except in lightening the vallet...
Ben
"If it works don't fix it! If it doesn't use a sledgehammer..."
How to ask a question, when posting them to a professional forum.
Only ask questions with yes/no answers if you want "yes" or "no"
Ben
"If it works don't fix it! If it doesn't use a sledgehammer..."
How to ask a question, when posting them to a professional forum.
Only ask questions with yes/no answers if you want "yes" or "no"
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1
- #12
There are two separate items to be aware of here:
1) Physical RAM
2) Virtual Address Space
A 32-bit system is limited to 4GB of physical RAM and also 4GB of Virtual Address Space. Each byte of RAM needs a byte in the Virtual Address Space to be in use by the OS. The problem is that when you first turn on the computer (long before Windows loads), the hardware memory manager called MMIO (Memory-Mapped Input Output) reserves some of that Virtual Address Space. For example, the system buses such as PCI-E, AGP, Hypertransport, etc., all need address space to function. In newer systems it's not uncommon for the MMIO to grab 1GB or more, stealing address space away from system RAM. Different system configurations will vary. I've seen some computers show 3.25GB available in Windows when 4GB was installed. But even given this chance, is it worth putting another gig in just to get a small increase? The answer heavily depends on the type of apps you use.
So, this is not a limitation of the OS. Unfortunately, it's a shortage caused by other devices in the system that interact directly with the BIOS. Using switches like /PAE or /3GB won't likely help either and could actually hurt overall performance. The second thread I listed below explains that.
Here are some recent threads that address the issue:
thread602-1457391
thread602-1452884
~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Einstein
[tab][navy]For posting policies, click [/navy]here.
1) Physical RAM
2) Virtual Address Space
A 32-bit system is limited to 4GB of physical RAM and also 4GB of Virtual Address Space. Each byte of RAM needs a byte in the Virtual Address Space to be in use by the OS. The problem is that when you first turn on the computer (long before Windows loads), the hardware memory manager called MMIO (Memory-Mapped Input Output) reserves some of that Virtual Address Space. For example, the system buses such as PCI-E, AGP, Hypertransport, etc., all need address space to function. In newer systems it's not uncommon for the MMIO to grab 1GB or more, stealing address space away from system RAM. Different system configurations will vary. I've seen some computers show 3.25GB available in Windows when 4GB was installed. But even given this chance, is it worth putting another gig in just to get a small increase? The answer heavily depends on the type of apps you use.
So, this is not a limitation of the OS. Unfortunately, it's a shortage caused by other devices in the system that interact directly with the BIOS. Using switches like /PAE or /3GB won't likely help either and could actually hurt overall performance. The second thread I listed below explains that.
Here are some recent threads that address the issue:
thread602-1457391
thread602-1452884
~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Einstein
[tab][navy]For posting policies, click [/navy]here.
mscallisto
Technical User
I believe your version of BIOS holds the RAM limits.
Maybe a later version of BIOS may support a larger limit.
Just a guess.
Maybe a later version of BIOS may support a larger limit.
Just a guess.
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