System Cannot Identify 4G RAM

[williamhuang]

Does 32-bit vista system support 4G memory?

My system can only identify 2G......

Is there any solution for that?

I don't want to change to 64-bit system~_~"

[W500]

search 3gig switch.  this was an option for xp, not sure about vista.  it allows the os to recognize 3 gigs of ram for any one application, then 1 gig is reserved for windows. 

[wjli2]

this shouldn't be happening with the new W series, it can therotically support 8 gig, you ram may be faulty. Go into BIOS how many gig of ram does it say you have????

Message Edited by wjli2 on 09-28-2008 10:32 AM

[williamhuang]

My BIOS and vista system information shows that I have 4G Memory

But the taskmgr shows I only have about 2.5G

I searched some explanations:

1. 32-bit vista  supports Maximum 4G Memory

2. However, it can only distributes about 3.12G to software

3. The rest of Memory is reserved for some hardware.

4. If you have many hardware that require shared memory, your memory appears in taskmgr will be less than 3.12G. (for me it only appears about 2.5G)

But I still have questions:

1. Is everybody here, who use 32-bit vista, have only 2.5G memory showed in taskmgr?

2. The graphic card of W500 has independent RAM. So, which hardware eat my Memory?

3.Except update to 64-bit vista, is there any way to let my system identify the rest of memory?

[Agotthelf Community Moderator]

Hello,

please install SP1 and all Vista updates. Then you´ll see your GB, but couldn´t use mor than 3,2-3,5.

Regards

Andreas

[williamhuang]

I am using SP1 and have installed all updates.

My tamskmgr still show me 2.5G of Memory......

Thank you all the same.

[Icepick]

williamhuang,

Your question pertains to the difference between 32-bit and 64-bit operating systems.  By design, 32-bit operating systems cannot address more than 4GB of memory....this is an OS architecture limitation and has nothing to do with hardware.

There are (2) places to check the installed physical memory:

1.  BIOS

2.  Microsoft System Information (Start --> Run --> msinfo32.exe)

Checking installed memory from System Properties will only show you the available memory after the OS has allocated to applications, processes, etc.  If BIOS and MS System Info do not show you the correct installed physical memory, then you could have a bad DIMM.

Reference MS KB 555223 for more in-depth memory allocation information.

Regards

[ZPrime]

---

Checking installed memory from System Properties will only show you the available memory after the OS has allocated to applications, processes, etc. 

---

While the rest of your post was correct, this isn't.

System Properties will show you how much physical RAM Windows is able to use for programs, kernel, etc.  The reason that a 4GB W500 on 32-bit Windows loses RAM is due to "artificial" limitations in Vista & XP (greater than SP2).  

In current consumer-editions of 32-bit Windows, there is a limitation of 4 GB of address space.  RAM obviously takes address space, but devices like your video card, SATA controller, wireless card, etc all need address space to function as well.   In XP SP2+ and Vista, this is a "hard" limit - everything above the 4GB mark is forcibly cut off by the operating system.  This limit is there because of buggy drivers, primarily from nVidia and ATI.  XP prior to SP2 and windows 2000 could handle a full 4GB of RAM - they do this by working with the motherboard to have the address space of some of the RAM remapped above the 4GB boundary.  (The accessory cards are hard-mapped to higher addresses near the 4GB limit for compatibility reasons.)  The problem with this remapping is that buggy drivers were written to assume that RAM would never be above a certain spot in address space, and so it would do Bad Stuff when you put it elsewhere.

So, on modern XP and Vista, you LOSE some RAM due to accessories.  Depending on the system, you can lose a lot - I only have about 2.5GB on 32-bit Vista, which is why I'm now running 64-bit instead.

[wjli2]

@ZPrime, i got told by Erik the guru now the mod that the Windows XP 32 bit can't use more than 3 gig, and any addressable space uses part of the 3 gig ram even if you install 4 gig of ram. 

 http://forums.lenovo.com/lnv/board/message?board.id=X_Series_Thinkpads&message.id=4021#M4021

I am getting very confused, with this.  

[erik Community SuperMod]

wjli2 - ZPrime is correct.   the 3~4GB memory space is reserved for hardware.   that's how it's always been.   what did i say in my post that confuses you?