4gig of Ram only showing as 3gig

slinki · 07-16-2006, 07:27 PM

This is my work workstation I use for 3D rendering/modeling stuff among other CAD related things.

Like the title says, I have installed 4 gig of RAM but it only shows as 3gig in the system properties as well as the task manager under physical memory in Windows.

- The MB is an Intel 915GEV. Memory is DDR2 4200 (1gb x 4) Dual channel.
- I'm not sure what CPUZ is finding but it looks like 2gig (2048) but it is also saying DUAL, strange.

Things I did:
1) Checked the MB manual to make sure it does take up to 4gig...it does.
2) Ran windiag for memory test and everything checked out.
3) removed each stick and booted with only one (1gig) stick at a time to test them all by themselves. No problems there.
4) checked in bios to see if the memory was showing up and it says 4gig.
5) Removed and reseated each stick.
6) Removed and moved them around in their dual pairs.

Any ideas?

ChemicalWarrior · 07-16-2006, 07:43 PM

Lol, Windows will only allow you to use up to 3GB, the other 1GB is reserved for the kernal I believe.

ChemicalWarrior · 07-16-2006, 08:11 PM

Did a bit more research and the other 1GB is reserved for PCI devices address space I believe, or something of that. You can search it on Google and you'll find tons of information about it.

Either way, I dont believe you can get past that barrier in 32 bit Windows (and anyway a process can not use over 2GB of memory), and I'm not one to suggest the hell hole that 64-bit Windows is.

{OF}Blong · 07-16-2006, 08:12 PM

what chem said. I think, however I could be wrong, that x64 version of windows allows 4 gig?

LoPo · 07-17-2006, 01:03 AM

Here's something that will help clarify for you all.

http://www.microsoft.com/whdc/system...AE/PAEmem.mspx

Soul · 07-17-2006, 08:07 AM

PAE ftw!

slinki · 07-23-2006, 03:35 AM

digging this thread back up since I have been away....

from the link lopo posted:

Quote:

Windows XP Professional and Windows Server 2003 Memory Support. The maximum amount of memory that can be supported on Windows XP Professional and Windows Server 2003 is also 4 GB.

Just to clarify, do I need to do something with the PAE or am I just SOL because of the type of processor and OS?
I'm a bit confused since that link is also talking about virtual memory.

dudio · 07-23-2006, 03:41 AM

Send me the memory for testing and analysis.

I will do this for you, 'cause you are cool,
and ARXors r0x0rs.

LoPo · 07-23-2006, 10:46 AM

You need to add the /3GB switch to your boot.ini.
/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. Some configurations of Microsoft Exchange Server 2003 and Microsoft Windows Server 2003 may require this switch.

This guy put together a fairly good list... of things it might break or what to expect.

http://www.gehrytechnologies.com/cat...rge_memory.htm

Soul · 07-23-2006, 12:12 PM

The 3gb switch caused us some headaches with mcafee