Windows XP
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My problem is that the PC only recognizes 2.5 gig of ram instead of the whole 4 gig. I contacted Dell about this and they suggested I have it upgraded to Windows XP 64 bit. If I do that alot of my software which is for 32 bit will not work. I am currently working on a Dimension 9200 with XP pro and it has 3 gigs ram and recognizes 3 gig. I have an older gateway pc at home that has 3 gig and recognizes 3gig.
Can anyone tell me what the problem is here and how to correct it? Thank you in advance for any advice yyou can give m.
Here is the answer I got from the Dell Representative:
REPLY FROM DELL REP.
I found this on the Microsoft website:
In 32 bit Windows operating systemshttp://en.wikipedia.org/wiki/operating_system , the total addressable
space available is 4GB. If you installed total 4GB memory, the system will detect less than 4GB of total memory because of address space allocation for other critical functions, such as:
- System BIOS (including motherboard, add-on cards, etc..)
- Motherboards resources
- Memory mapped I/O
- Configuration for AGP/PCI-Ex/PCI
- Other memory allocations for PCI devices
Different onboard devices and different add-on cards (devices) will result of different total memory size. e.g. more PCI cards installed will require more memory resources, resulting of less memory free for other uses.
This limitation applies to most chipsets & Windows XPhttp://en.wikipedia.org/wiki/Windows_XP /Vista 32-bit version operating systems.
If you install a Windows operating system, if more than 3GB memory is required for your system, then the below conditions should be met:
1. The memory controller which supports memory swap functionality is used. The latest chipsets like Intel 975X, 955X, Nvidia NF4 SLI Intel Edition, Nvidia NF4 SLI X16, AMD K8 and newer architectures can support the memory swap function.
2. Windows XP Pro X64http://en.wikipedia.org/wiki/x86-64 Ed. (64-bit), Windows Vista 64, or other OS which can address more than 4GB memory.
I am pasting below the specs on my new computer.
PWS T3400 525W (32bit)
Intel" Core®2 Extreme QX6850 (3.00GHz/1333MHz/2X4MB L2) 525W, Genuine Windows Vista® Ultimate Downgrade, XP Pro Installed, English
PWS T3400 525W (32bit) Intel" Core®2 Extreme QX6850 (3.00GHz/1333MHz/2X4MB L2) 525W
Operating System: Genuine Windows Vista® Ultimate Downgrade, XP Pro Installed, English
Chassis Configuration and 1394: Mini-Tower Chassis Configuration w/ 1394 Card
Memory: 4GB, 800MHz, DDR2 SDRAM Memory, ECC (4 DIMMS)
Keyboard: Enhanced USB Multimedia, 8 Hot Keys
Graphic Cards: 512MB PCIe x16 nVidia Quadro FX1700, Dual Monitor DVI Capable
Boot Hard Drive: 750GB SATA 3.0Gb/s with NCQ and 16MB DataBurst Cache"
Hard Drive Configuration: C1, All SATA, NO RAID for 1 Hard Drive
Floppy Drive and Media Card Reader Options: 3.5 inch 1.44MB Floppy Drive
Mouse: New Dell USB Optical Mouse with scroll, All Black Design
Modem: Dell Data/Fax PCI Modem
CD-ROM, DVD, and Read-Write Devices: 16XDVD AND 16XDVD+/-RW, w/ Cyberlink PowerDVD" and Roxio Creator"
Sound Card: SoundBlaster X-FI XtremeMusic" (D)w/Dolby#173; Digital 5.1
Speakers: Logitech Z-4 Speaker System
Wireless: Dell 1505 Wireless-N PCIe Card
Resource CD: Resource CD and DVD contains Diagnostics and Driver for Dell Precision Syst
Labels: Windows Vista® Premium
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32 bit XP will see a maximum of 3.5 GB (if you have 4GB installed) - 64-bit will see all memory installed and be able to address it. Vista can see up to 8GB with Vista 32 bit.
So, you are starting with 3.5 not 4gb (because of OS limitations) and you now need to subtract Video Cache, DVD cache, etc from main memory - each PCI card you have also eats at least 256MB. Very common to see XP 32 bit systems report only 3GB, 2.75, or 2.5GB
I am not quite sure how that article came up with its information, but it mentions 64-bit XP, not vista, also keep in mind the date of the article. Lots has changed in hardware since 2005. All processors are 64-bit with 64-bit chipsets.
Back to the poster;
As to the allocation of RAM, there are like the reasons listed in the article, (though I have never ever seen a pci card take up that much ram, but that is just maybe my experience) is your ram matched pairs? Like do you have dual channel ram? single channel? why bothering with ECC ram on a desktop?
As stated above, check the RAM reported in the bios or POST, another thing could be checking a BartPE/Knoppix boot CD and check the allocation there. You could narrow it down to if even XP is the problem (my bet is it isn't but I have been wrong before).
To further educate you both, I'll try to give a short explanation as to why a 32-bit-x86 OS with 4 GByte (or more) won't display thefull amount of system memory within task manager/perfmon.
A 32-bit Windows XP or Vista OS offers an address-space of 2^32 bytes. Inside this address space are not only the addresses of physically available storage cells, but also the I/O addresses of interfaces and hardware-components. Over those I/O addresses the OS communicates with every PCI-, PCIe- or AGP-card, chipset integrated I/O-controllers, and all MotherBoard components. The needed address scopes are reserved by the mainboard-BIOS during the system start phase underneath the highest possible 32-bit address of 0xffffffff.
When only 3 GByte physical memory are installed there aren't any conflicts. But when the RAM is enhanced to 4 GByte or more, the PCI-address-hole covers parts of the system memory, which the OS can't use. The PCI-address-hole will get much bigger the more hardware-components are installed on a system. Graphic cards (GPUs) with lots of local memory do usually allocate the most of the cake here.






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"So, if your video adapter has 512MB of RAM (like mine does), your maximum memory is going to at most be 3.5GB, because Vista has to use 512MB of that address space to address your video memory. It?ll actually be lower than the 3.5GB because there are other hardware resources that need address space, too. So, it never hurts to fill your computer with 4GB of RAM?you?ll definitely get the max, but you won?t be able to address it all. You probably won?t be able to address much more than 3GB, and you might not be able to address more than 2GB.
The paper also mentions something interesting about 64-bit computers. Basically, depending on the hardware, you might be limited to 4GB of RAM even if you install 64-bit Windows Vista:"
last word in your post... is what?
I never questioned the 4GB limit, i did question the validity of you comparing a paper written about XP to Vista.
As to the allocation of ram in xp 64 (which i use with 4GB of ram allocating ALL of it, not 3.5, not 3, not 2)
But this is detracting from the poster's question.
read my info about checking the RAM for problems before blaming XP.
Exactly my point - It is not an XP issue but a 32-bit OS issue - Vista or XP! And not one that anyone can solve as it is by design.

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4GB of ram reporting as 2.5Gb is bad
So here is the list of troubleshooting steps
(if not dual channel RAM)
Take 1 GB out.. does it display as 3gb?
(if dual channel)
run a copy of Knoppix or BartPe and check the ram listing there. (BartPE is built using a WinXP core so it will have the "same" potential limitations but could give a slightly different result)
If the Knoppix/BartPE report the SAME response as regular XP, you know it is not the OS but the RAM itself.
If removing 1 GB of ram fixes it, then you know it was XP (32-bit) and you should just upgrade to x64 or ditch the extra GB.
One last note to jss, please don't get into a pissing match over your info, I am trying to help the poster and give him unbiased information that is current. I don't need you to argue with me about what YOU did or didn't say. Please just let it go and act like an adult.
PamelaFox - You can download BartPE from http://www.nu2.nu/pebuilder/ and it includes instructions.






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www.knoppix.net/
BartPE = www.nu2.nu/pebuilder/
Bart is sort of a minimal install of XP that is designed to take all the frills out for testing. Being that it is built onto a CD, you can't have viruses on it, so it boots wonderfully.
Being that taking 1 GB out didn't fix it, that is Bad. That means Windows (being that taking 1 stick out gets it below the 3GB limit) isn't the problem and most likely it is the RAM stick being bad.
I suggest still trying knoppix or Bart
Good luck.
Now you seem to misunderstand something - you said "they suggested I have it upgraded to Windows XP 64 bit. If I do that alot of my software which is for 32 bit will not work" - this is not true. MOST (but NOT ALL) 32bit software works just fine on a 64 bit version of Windows. Things that do not are either hardware related (including those programs that use drivers, such as some antivirus programs) and programs that have 16bit installers - 16 bit programs won't run at all.
And while anything is possible, I SERIOUSLY doubt you have any hardware issues whatsoever.
Also when 1 GB was removed (effecting the total below the 3.5gb limit) it STILL showed 2.5, this indicates it is not a 32-bit XP issue.
On the other hand, if the ram was dual channel, and mismatched, that could also show incorrect numbers.
To PAM, can you see all 4GB in the BIOS/POST? Though this doesn't rule out bad ram, it can rule out mismatched dual channels (most of the time).

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Krazy - The limit, I beleive, is 3GB, not 3.5. Removing 1GB of RAM would still put PAM at 3GB or greater.
Those diagnostic tools are perfect for a situation such as this.






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Knoppix and BartPE aren't installed - they are booted from - Knoppix never installs anything and BartPE only installs a small helper application to help you build the CD.
Memory Speed = 800 Mhz
Memory Channel Mode = Dual Symmetric
Memory Technology = DDR2 SDRAM (ECC)
Under this there is a table box with the categories, Memory Slot, Size, ECC, Rank, Type, Organization
They all list the same 1GB, Yes, 2, Unbuffered, x8. However under the memory slot the order is: DIMM 1, DIMM 3, DIMM 2, DIMM4. Not sure if that makes a difference.
Processor Info
Processor Type = Intel (R) Core (TM)2 Extreme CPU Q6850 @ 3.00GHz
Processor Clock Speed = 3.0 GHz
Processor Bus Speed = 1333 MHz
Processor L2 Cache = 8 MB
Processor L3 Cache = 0 B
Multiple Core capable = yes (Quad)
Hyperthreading capable = no
64-bit technology = Yes (Intel EM64T)
Do you think I have bad ramm? Or is it because my video card is so large? Should I still run the Knoppix or BartPe. And what am I looking for?
Thank you all so much for being so patient with me.

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You do not have bad RAM, it is simply a limitation of 32 bit operating systems. If you want the large video card and 4+ GB of memory to be addressable, move to 64 bit OS.
Thanks,
jss1199






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I'm sorry you had to go through so many cycles with Dell to receive an answer from them - the answer, as I posted, is truley a level 1 support issue and should have been answered by Dell upon first contact with them.
Where did you purchase the Dell computer? As you had an open case with Dell, you can argue (takes a bit of force) the point that it took Dell two weeks to answer you so the decision to return was delayed only by their response time. Also, take notice of the date on your packing slip/invoice - this is the date that matters. You have 30 days to return the purchase from the date indicated on the packing slip/invoice - not from the order date. Knowing Dell, the order placed on June 18 was not filled until a later date...
I was told by the level 2 tech at dell with the smaller video card I would gain at least 3.2 - 3.7 ram. I hope he wasn't telling a lie. He said the only reason I would need a 512 card would be if I was editing movies or using autocad program. I don't do either. All I use it for is our family photos, which I use photo shop elements to correct older photos and I use it for our music library.
I also talked to our IT person out here and he said Dell is giving me the run around. He said the 512 card uses 512 plus holds an additional 512 of ram like a mirror. He said the tech should have told me to go into the bios and release that mirrow ram and not hold it and the problem would be solved. You ever heard doing this before?
I'm really disappointed because I don't like windows vista and the only reason I purchased the PC now is because they were ending XP. I saved 2 years to purchase this PC. I paid $3,500.00 cash for it so yes I am really disappointed. I am going to call Dell tonight and try to talk to a level 3 tech and see if he knows about the bios tweaking thing.
Do you personally think I just just suck it up and keep the machine? Thank you. Any advice would be appreciated.

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I have not heard of the concept of RAM used like a mirror with respect to video cards. It is more likely that you can disable various unused ports in the BIOS, which will reduce their footprint in the RAM taken up by hardware.
$3500 for a PC these days is really excessive. You probably could get a $2000 machine custom built that would be at least as fast. I and a number of other experts could configure such a setup easily.






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Windows XP
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Microsoft Windows XP is the sixth release of the NT series of operating systems, and was the first to be marketed in a variety of editions: XP Home and XP Professional, designed for business and power users. The advanced features in XP Professional are generally disabled in Home Edition, but are there and can be activated. There were two 64-bit editions, an embedded edition and a tablet edition.