Inspirion 530 + 4GB Ram needs a 'memory remap'!

Question

I'm using a bigmem kernel, then I could use the whole memory (4GB).

When linux starts, it check the available memory, but the bios report a wrong memory map:

BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009e800 (usable)
BIOS-e820: 000000000009e800 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 00000000cfe90000 (usable)
BIOS-e820: 00000000cfe90000 - 00000000cfee3000 (ACPI NVS)
BIOS-e820: 00000000cfee3000 - 00000000cfef0000 (ACPI data)
BIOS-e820: 00000000cfef0000 - 00000000cff00000 (reserved)
BIOS-e820: 00000000e0000000 - 00000000f0000000 (reserved)
BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved)
2430MB HIGHMEM available.
896MB LOWMEM available.

I read the faq, but I want to ask: do you could update your bios and add the "memory remap for pci devices?"

Please take a look to this link http://support.microsoft.com/kb/929605:

"• The BIOS must support the memory remapping feature. The memory remapping feature allows for the segment of system memory that was previously overwritten by the Peripheral Component Interconnect (PCI) configuration space to be remapped above the 4 GB address line. This feature must be enabled in the BIOS configuration utility on the computer. View your computer product documentation for instructions that explain how to enable this feature. Many consumer-oriented computers may not support the memory remapping feature. No standard terminology is used in documentation or in BIOS configuration utilities for this feature. Therefore, you may have to read the descriptions of the various BIOS configuration settings that are available to determine whether any of the settings enable the memory remapping feature."

Best regards

Linicks · Answer

Once the system has booted, what does it report the memory as? > free Nick

Linicks · Answer

But I don't know what your issue is? You have 4G of memory? Just post a: > free Nick

Linicks · Answer

I don't think you need 64G set for 4G ram...

Here is my desktop:

CONFIG_HIGHMEM4G=y
# CONFIG_HIGHMEM64G is not set
CONFIG_HIGHMEM=y

EDIT: Have a read of this:

http://kerneltrap.org/node/2450

Nick

Message Edited by Linicks on 11-18-2007 08:29 PM

Kbyte · Answer

I've also tried with 4GB Highmem option :( (I've used 64GB because it enable the PAE support). Do you have a Inspirion 530? I hope that some of 'dell' guys read this message and tell us if they will work to a bios upgrade (if the hardware support the pci memory address remapping).

Kbyte · Answer

free -m total used free shared buffers cached Mem: 3289 2835 453 0 51 2324 And these are the bigmem options for that kernel: CONFIG_HIGHMEM64G=y CONFIG_HIGHMEM=y CONFIG_X86_PAE=y CONFIG_HIGHPTE=y

Kbyte · Answer

Yes, I've 4GB of memory.

This is the free result:

free
total used free shared buffers cached
Mem: 3368124 3252160 115964 0 40392 2683444
-/+ buffers/cache: 528324 2839800
Swap: 4883720 192 4883528

Please try this test:

dmesg | grep BIOS-e820

If your bios detects the memory correctly and supports the pci memory remapping you will see three rows with "usable" label.

Linicks · Answer

Well, I only have 1.5G, but still, you assumption is wrong:

nick$ dmesg | grep BIOS-e820
BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)
BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 000000005fff0000 (usable)
BIOS-e820: 000000005fff0000 - 000000005fff3000 (ACPI NVS)
BIOS-e820: 000000005fff3000 - 0000000060000000 (ACPI data)
BIOS-e820: 00000000ffff0000 - 0000000100000000 (reserved)

Anyway, read this thread - it explains what I have trying to say better - you DO have 4G ram in use...

http://www.linuxquestions.org/questions/linux-hardware-18/4gb-ram-not-showing-300277/

Nick

Kbyte · Answer

I'm wrong? :)

Lol, you don't have 4GB and tell me that I'm wrong :)

I've 4GB, but the bios reports only 3,2GB because of the pci memory allocation map, that have to be relocated over 4GB to allow me to see the whole memory.

This is a bios memory report of some system with 4GB:

BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009fc00 (usable)
BIOS-e820: 000000000009fc00 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000e6000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 00000000b7fd0000 (usable)
BIOS-e820: 00000000b7fd0000 - 00000000b7fde000 (ACPI data)
BIOS-e820: 00000000b7fde000 - 00000000b8000000 (ACPI NVS)
BIOS-e820: 00000000fec00000 - 00000000fec01000 (reserved)
BIOS-e820: 00000000fee00000 - 00000000fee01000 (reserved)
BIOS-e820: 00000000ff780000 - 0000000100000000 (reserved)
BIOS-e820: 0000000100000000 - 0000000145000000 (usable)

Look the last row.

This is a BIOS problem, do you understand?

Message Edited by Kbyte on 11-19-2007 02:27 PM

jesuscl · Answer

Hello,
I have the same problem.

I bought an Inspiron 530s with 4GB Ram with Windows Vista 32bits.

I have only available 3.25 GB. I thought that it was a problem with Windows 32bits OSes.

Yesterday I installed Ubuntu 7.10 64 bits and surprisingly doing a free -m on console show me only 3.2 GB

Regards

jesuscl · Answer

Hello,

A person from Dell support says that they doesn't know about a memory remap problem with this model. However he says that I can try to install the last BIOS update:

http://support.euro.dell.com/support/downloads/download.aspx?c=es&l=es&s=gen&releaseid=R167100&SystemID=INSP_DSKTP_D530S&servicetag=&os=WLH&osl=sp&deviceid=14181&devlib=0&typecnt=0&vercnt=3&catid=-1&impid=-1&formatcnt=1&libid=1&fileid=225972

I can't check it now, because currently I'm on the office and the Inspiron is my home Desktop computer. The updated BIOS version is the 1.05, I think that this version is the same that I have.

I have been Googling and I've found some people with similar problems, but not exactly with a Dell computer. The problem was that the mother board includes some Intel chipset that is bad recognized by the kernel. Adding this to some blacklist in the kernel could make to recognize the full RAM (or almost) in the system.

This is the link to the page found:

http://ubuntuforums.org/showthread.php?t=375853&page=2

Look at the second comment on the page referenced.

Maybe this is not exactly our problem but it looks similar.

Regards

Linux General

Inspirion 530 + 4GB Ram needs a "memory remap"!

Was this post helpful?