where did my memory go?
in [Asus]
|
Prev: stupid fan question
Next: Looking for cpu fan for 478
From: coltrane on 15 May 2010 11:15 this might be more of a generic mainboard question but that group doesn't seem active. I have an asus p7p55d-e mb running windows xp. I have 2 G.Skill 2GB sticks. Sandra correctly shows 2 X 2GB, but when I view the amount of memory in the system properties window it shows 2.99 GB. I have also run RightMark Memory Stability test and that shows 2047GB total memory with available physical of 2047GB. so my question is where did my memory go ( too young for Alzheimers! ) thanks john
From: Paul on 15 May 2010 12:38 coltrane wrote: > this might be more of a generic mainboard question but that group > doesn't seem active. > I have an asus p7p55d-e mb running windows xp. I have 2 G.Skill 2GB > sticks. Sandra correctly shows 2 X 2GB, but when I view the amount of > memory in the system properties window it shows 2.99 GB. > I have also run RightMark Memory Stability test and that shows 2047GB > total memory with available physical of 2047GB. > so my question is where did my memory go ( too young for Alzheimers! ) > > > thanks > john First, let's start with the hardware. Processors/chipsets, with a working PAE implementation, support 36 bit or more addressing. That allows a mapping from a 4GB virtual space (32 bit virtual address), to a much larger physical address. That makes it possible, for a 32 bit OS, to support more than 4GB of memory. You could support 64GB this way. 32 bit virtual ---> page_tables and translation ---> 36 bit physical Microsoft has PAE turned on for other reasons. But in doing so, they chose not to support more than 4GB physically. It helps them separate their more expensive server OS products, from a desktop products. We wouldn't want businesses running their servers, with a $99 copy of WinXP Home :-) http://www.geoffchappell.com/viewer.htm?doc=notes/windows/license/memory.htm From the 4GB of physical addresses Microsoft gives you, you need address space for things like the video card. So that comes out of the address space limit first. The remaining space, after all busses have addresses assigned, is available to address memory. Right now, you have 4GB physical memory installed, but roughly 1.01GB of that memory, there is no way to get to it. No address generated by the processor, is currently able to trigger an access to those 1.01GB of locations. It is like building houses in the middle of no-where, with no "streets" to get to the houses. If you used some other 32 bit OS, with a working PAE implementation, you may be able to access more of the memory. ******* With regard to single process and maximum memory usage, there are a couple limits there. The kernel/user space split must be adjusted, to make more of the memory available. The RightMark program must be compiled to be large address aware, to use more than 2GB. So you probably need to change something in boot.ini, to allow the RightMark program to use more memory. http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx Memory type Limit in 32-bit Windows User-mode virtual 2 GB address space for each 32-bit process Up to 3 GB with IMAGE_FILE_LARGE_ADDRESS_AWARE and 4GT "How 4GT Works" http://technet.microsoft.com/en-us/library/cc784475(WS.10).aspx The /3GB boot.ini switch, changes the split between kernel and user space virtual addresses. In my experiments here, I wasn't able to get anything useful from it. I didn't have any large address aware applications at the time. Other applications I had, still had the 2GB limit, because they weren't large address aware. "Available switch options for the Windows XP boot.ini" http://support.microsoft.com/kb/833721 "/3GB This switch forces x86-based systems to allocate 3 GB of virtual address space to programs and 1 GB to the kernel and to executive components. A program must be designed to take advantage of the additional memory address space. With this switch, user mode programs can access 3 GB of memory instead of the usual 2 GB that Windows allocates to user mode programs. The switch moves the starting point of kernel memory to 3 GB." If you switch to a 64 bit OS, (almost) all your problems will be solved. Don't buy WinXP x64, as that one is "half finished". Read the reviews about WinXP x64, before even thinking about buying it. Later 64 bit versions of OSes, may work better. So if you really feel the need to access every byte of your 4GB of memory, it'll cost you a new OS. (Customer Reviews for Microsoft Windows XP Professional 64-bit) http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16832116378 If I was doing testing here, this is the configuration I would use with my copy of WinXP x32. 1) Install 4GB physical memory. 2) Remove honking big PCI Express video card(s). Then, I'd install my FX5200 PCI video card with only 128MB of memory on board. This would make around 3.5GB of system memory addressable by the hardware decoder. With its tiny onboard memory, this video card uses less bus address space. 3) Turn on the /3GB switch. 4) Test with a large address aware application. With luck, I see somewhere between 2GB and 3GB of memory allocated to that single application. HTH, Paul
From: coltrane on 15 May 2010 14:53 On 5/15/2010 12:38 PM, Paul wrote: > coltrane wrote: >> this might be more of a generic mainboard question but that group >> doesn't seem active. >> I have an asus p7p55d-e mb running windows xp. I have 2 G.Skill 2GB >> sticks. Sandra correctly shows 2 X 2GB, but when I view the amount of >> memory in the system properties window it shows 2.99 GB. >> I have also run RightMark Memory Stability test and that shows 2047GB >> total memory with available physical of 2047GB. >> so my question is where did my memory go ( too young for Alzheimers! ) >> >> >> thanks >> john > > First, let's start with the hardware. Processors/chipsets, with a working > PAE implementation, support 36 bit or more addressing. That allows a > mapping from a 4GB virtual space (32 bit virtual address), to a much larger > physical address. That makes it possible, for a 32 bit OS, to support > more than 4GB of memory. You could support 64GB this way. > > 32 bit virtual ---> page_tables and translation ---> 36 bit physical > > Microsoft has PAE turned on for other reasons. But in doing so, they > chose not to support more than 4GB physically. It helps them > separate their more expensive server OS products, from a desktop > products. We wouldn't want businesses running their servers, with > a $99 copy of WinXP Home :-) > > http://www.geoffchappell.com/viewer.htm?doc=notes/windows/license/memory.htm > > > From the 4GB of physical addresses Microsoft gives you, you need > address space > for things like the video card. So that comes out of the address space > limit first. The remaining space, after all busses have addresses assigned, > is available to address memory. > > Right now, you have 4GB physical memory installed, but roughly 1.01GB > of that memory, there is no way to get to it. No address generated > by the processor, is currently able to trigger an access to those > 1.01GB of locations. It is like building houses in the middle of > no-where, with no "streets" to get to the houses. > > If you used some other 32 bit OS, with a working PAE implementation, > you may be able to access more of the memory. > > ******* > > With regard to single process and maximum memory usage, there are > a couple limits there. The kernel/user space split must be adjusted, > to make more of the memory available. The RightMark program must be > compiled to be large address aware, to use more than 2GB. So you probably > need to change something in boot.ini, to allow the RightMark program to > use more memory. > > http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx > > Memory type Limit in 32-bit Windows > > User-mode virtual 2 GB > address space for > each 32-bit process Up to 3 GB with > IMAGE_FILE_LARGE_ADDRESS_AWARE > and 4GT > > "How 4GT Works" > http://technet.microsoft.com/en-us/library/cc784475(WS.10).aspx > > The /3GB boot.ini switch, changes the split between kernel and > user space virtual addresses. In my experiments here, I wasn't > able to get anything useful from it. I didn't have any large > address aware applications at the time. Other applications I had, > still had the 2GB limit, because they weren't large address aware. > > "Available switch options for the Windows XP boot.ini" > http://support.microsoft.com/kb/833721 > > "/3GB > > This switch forces x86-based systems to allocate 3 GB of virtual > address space to programs and 1 GB to the kernel and to executive > components. A program must be designed to take advantage of the > additional memory address space. With this switch, user mode > programs can access 3 GB of memory instead of the usual 2 GB > that Windows allocates to user mode programs. The switch moves > the starting point of kernel memory to 3 GB." > > If you switch to a 64 bit OS, (almost) all your problems will > be solved. Don't buy WinXP x64, as that one is "half finished". > Read the reviews about WinXP x64, before even thinking about > buying it. Later 64 bit versions of OSes, may work better. > So if you really feel the need to access every byte of > your 4GB of memory, it'll cost you a new OS. > > (Customer Reviews for Microsoft Windows XP Professional 64-bit) > http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16832116378 > > If I was doing testing here, this is the configuration I would use > with my copy of WinXP x32. > > 1) Install 4GB physical memory. > > 2) Remove honking big PCI Express video card(s). Then, I'd install > my FX5200 PCI video card with only 128MB of memory on board. > This would make around 3.5GB of system memory addressable by > the hardware decoder. With its tiny onboard memory, this video > card uses less bus address space. > > 3) Turn on the /3GB switch. > > 4) Test with a large address aware application. With luck, > I see somewhere between 2GB and 3GB of memory allocated > to that single application. > > HTH, > Paul sure glad I paid for 4gb thinking I would get better performance. I'd switch to Windows7 x64 but the driver/software compatibility would be a nightmare. My work is all windows based so I can't move to a flavor of linux. I remember the issue of video card memory space from 35 years ago. I thought that problem would have been addressed by now. Actually my video memory is 256mb. I have an NVidia Geforce 8500GT. ARGH! thanks for the help (again) john
From: GMAN on 15 May 2010 15:05 In article <4beeed81$0$31276$607ed4bc(a)cv.net>, coltrane <tendengarci(a)yahoo.com> wrote: >On 5/15/2010 12:38 PM, Paul wrote: >> coltrane wrote: >>> this might be more of a generic mainboard question but that group >>> doesn't seem active. >>> I have an asus p7p55d-e mb running windows xp. I have 2 G.Skill 2GB >>> sticks. Sandra correctly shows 2 X 2GB, but when I view the amount of >>> memory in the system properties window it shows 2.99 GB. >>> I have also run RightMark Memory Stability test and that shows 2047GB >>> total memory with available physical of 2047GB. >>> so my question is where did my memory go ( too young for Alzheimers! ) >>> >>> >>> thanks >>> john >> >> First, let's start with the hardware. Processors/chipsets, with a working >> PAE implementation, support 36 bit or more addressing. That allows a >> mapping from a 4GB virtual space (32 bit virtual address), to a much larger >> physical address. That makes it possible, for a 32 bit OS, to support >> more than 4GB of memory. You could support 64GB this way. >> >> 32 bit virtual ---> page_tables and translation ---> 36 bit physical >> >> Microsoft has PAE turned on for other reasons. But in doing so, they >> chose not to support more than 4GB physically. It helps them >> separate their more expensive server OS products, from a desktop >> products. We wouldn't want businesses running their servers, with >> a $99 copy of WinXP Home :-) >> >> http://www.geoffchappell.com/viewer.htm?doc=notes/windows/license/memory.htm >> >> >> From the 4GB of physical addresses Microsoft gives you, you need >> address space >> for things like the video card. So that comes out of the address space >> limit first. The remaining space, after all busses have addresses assigned, >> is available to address memory. >> >> Right now, you have 4GB physical memory installed, but roughly 1.01GB >> of that memory, there is no way to get to it. No address generated >> by the processor, is currently able to trigger an access to those >> 1.01GB of locations. It is like building houses in the middle of >> no-where, with no "streets" to get to the houses. >> >> If you used some other 32 bit OS, with a working PAE implementation, >> you may be able to access more of the memory. >> >> ******* >> >> With regard to single process and maximum memory usage, there are >> a couple limits there. The kernel/user space split must be adjusted, >> to make more of the memory available. The RightMark program must be >> compiled to be large address aware, to use more than 2GB. So you probably >> need to change something in boot.ini, to allow the RightMark program to >> use more memory. >> >> http://msdn.microsoft.com/en-us/library/aa366778(VS.85).aspx >> >> Memory type Limit in 32-bit Windows >> >> User-mode virtual 2 GB >> address space for >> each 32-bit process Up to 3 GB with >> IMAGE_FILE_LARGE_ADDRESS_AWARE >> and 4GT >> >> "How 4GT Works" >> http://technet.microsoft.com/en-us/library/cc784475(WS.10).aspx >> >> The /3GB boot.ini switch, changes the split between kernel and >> user space virtual addresses. In my experiments here, I wasn't >> able to get anything useful from it. I didn't have any large >> address aware applications at the time. Other applications I had, >> still had the 2GB limit, because they weren't large address aware. >> >> "Available switch options for the Windows XP boot.ini" >> http://support.microsoft.com/kb/833721 >> >> "/3GB >> >> This switch forces x86-based systems to allocate 3 GB of virtual >> address space to programs and 1 GB to the kernel and to executive >> components. A program must be designed to take advantage of the >> additional memory address space. With this switch, user mode >> programs can access 3 GB of memory instead of the usual 2 GB >> that Windows allocates to user mode programs. The switch moves >> the starting point of kernel memory to 3 GB." >> >> If you switch to a 64 bit OS, (almost) all your problems will >> be solved. Don't buy WinXP x64, as that one is "half finished". >> Read the reviews about WinXP x64, before even thinking about >> buying it. Later 64 bit versions of OSes, may work better. >> So if you really feel the need to access every byte of >> your 4GB of memory, it'll cost you a new OS. >> >> (Customer Reviews for Microsoft Windows XP Professional 64-bit) >> http://www.newegg.com/Product/ProductReview.aspx?Item=N82E16832116378 >> >> If I was doing testing here, this is the configuration I would use >> with my copy of WinXP x32. >> >> 1) Install 4GB physical memory. >> >> 2) Remove honking big PCI Express video card(s). Then, I'd install >> my FX5200 PCI video card with only 128MB of memory on board. >> This would make around 3.5GB of system memory addressable by >> the hardware decoder. With its tiny onboard memory, this video >> card uses less bus address space. >> >> 3) Turn on the /3GB switch. >> >> 4) Test with a large address aware application. With luck, >> I see somewhere between 2GB and 3GB of memory allocated >> to that single application. >> >> HTH, >> Paul >sure glad I paid for 4gb thinking I would get better performance. >I'd switch to Windows7 x64 but the driver/software compatibility would >be a nightmare. My work is all windows based so I can't move to a flavor >of linux. >I remember the issue of video card memory space from 35 years ago. I >thought that problem would have been addressed by now. >Actually my video memory is 256mb. I have an NVidia Geforce 8500GT. > >ARGH! > >thanks for the help (again) > >john > Go into your bios setup and under advanced, look for the setting, MEMORY REMAP FEATURE. If its enabled, choose disbled and try that to see if you get About 3GB memory showing up available. If its disabled currently, try enabling it and see what you get.
From: Barry Watzman on 15 May 2010 16:10
Something in your system is likely limiting you to 32-bit operation (most likely either the CPU or the OS). This is 4GB. But the hardware REQUIRES some memory space, which means that all of the 4GB of memory space cannot be occupied by RAM memory; some of it is used by other devices (BIOS, motherboard, sound card, network card, video card). You show what's left, and perhaps only the part of what's left that is contiguous from address zero to the first address used by any hardware device. Which is normally about 3GB. The only way to get more is to use a 64-bit system. In particular that means a 64-bit CPU (most are) and a 64-bit OS (most are not). Now, that said, note that: 1. If you go the 64 bit route, expect some compatibility issues. Possibly very serious and not resolveable. 2. If you go the 64-bit route, DO NOT expect to see any benefits; for most people, 3GB of RAM is more than they need. Are there exceptions? Sure, lots of them (and more everyday). BUT, that doesn't change the fact that for probably more than 80% of people, there is no real benefit to a 64 bit system with more than 3GB of available RAM memory. coltrane wrote: > this might be more of a generic mainboard question but that group > doesn't seem active. > I have an asus p7p55d-e mb running windows xp. I have 2 G.Skill 2GB > sticks. Sandra correctly shows 2 X 2GB, but when I view the amount of > memory in the system properties window it shows 2.99 GB. > I have also run RightMark Memory Stability test and that shows 2047GB > total memory with available physical of 2047GB. > so my question is where did my memory go ( too young for Alzheimers! ) > > > thanks > john |