Ubuntu 9.10 Only Sees 244 MB RAM, while BIOS and Windows Sees 1.5 GB

I have 1.5 GB of RAM installed on an older Dell, Pentium 4. I just installed Ubuntu 9.1 and the system is only seeing 244 MB of RAM, even though there is 1.5 GB on the system. The BIOS sees all of it. I ran a Knoppix disc and it only saw 25 MB upon booting.

I made no particular changes to the installation taht would affect this. I looked through the BIOS and the only setting I could see was the AGP aperture. Not even sure what this is.

Anyone know where I went wrong?

I also tried moving the memory modules around on the board. Booted with the 1 GB stick, still saw 244 MB.

NOTE - This same system, except for the hard drive, had Windows XP running on it. The user who ran it said that the RAM was good and always showed 1.5 GB.

Here is sudo cat /proc/meminfo

MemTotal: 250064 kB
MemFree: 3832 kB
Buffers: 13356 kB
Cached: 52216 kB
SwapCached: 19676 kB
Active: 91504 kB
Inactive: 113884 kB
Active(anon): 60572 kB
Inactive(anon): 82156 kB
Active(file): 30932 kB
Inactive(file): 31728 kB
Unevictable: 0 kB
Mlocked: 0 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 250064 kB
LowFree: 3832 kB
SwapTotal: 4883720 kB
SwapFree: 4781204 kB
Dirty: 496 kB
Writeback: 720 kB
AnonPages: 123796 kB
Mapped: 23368 kB
Slab: 17248 kB
SReclaimable: 7932 kB
SUnreclaim: 9316 kB
PageTables: 5304 kB
NFS_Unstable: 0 kB
Bounce: 0 kB
WritebackTmp: 0 kB
CommitLimit: 5008752 kB
Committed_AS: 740372 kB
VmallocTotal: 770600 kB
VmallocUsed: 26008 kB
VmallocChunk: 662544 kB
HugePages_Total: 0
HugePages_Free: 0
HugePages_Rsvd: 0
HugePages_Surp: 0
Hugepagesize: 4096 kB
DirectMap4k: 114128 kB
DirectMap4M: 147456 kB

Hardware configuration:

• eMachine T3958
• Intel Celeron D 340, 3 GHz processor, Socket 478
• 1.5 GB RAM (one 1 GB and two 256 MB sticks)

I posted dmesg and hwinfo --short on pastebin.

EDIT - I found out some additional, rather important information just now. My monitor configuration was such that, when I changed my monitor to the second channel of a 1>2 VGA splitter, I see additional information upon booting:

Alert! OS install mode enabled.
Amount of available memory limited to 256MB.

I'm not sure what this means or from where it originated. Do I have a BIOS problem?

EDIT - So upon searching through the web and my BIOS, I found a setting in the BIOS called "Install Mode." This was turned "on" for some reason. Not sure if I did it or it changed as default when I installed the new hard disk. Anyway, this was my problem the whole time. Errgh. Thanks for everyone's help!

Solution 1:

The BIOS RAM map is only telling Linux that there's only 256MB of memory available:

BIOS-e820: 0000000000000000 - 00000000000a0000 (usable)    : 640k
BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 000000000ff74000 (usable)    : 260560k
BIOS-e820: 000000000ff74000 - 000000000ff76000 (ACPI NVS)
BIOS-e820: 000000000ff76000 - 000000000ff97000 (ACPI data)
BIOS-e820: 000000000ff97000 - 0000000010000000 (reserved)
BIOS-e820: 00000000fec00000 - 00000000fec10000 (reserved)
BIOS-e820: 00000000fecf0000 - 00000000fecf1000 (reserved)
BIOS-e820: 00000000fed20000 - 00000000fed90000 (reserved)
BIOS-e820: 00000000fee00000 - 00000000fee10000 (reserved)
BIOS-e820: 00000000ffb00000 - 0000000100000000 (reserved)

Ideally, fix your BIOS. Or, try booting with mem=1536m specified as an additional kernel parameter. You may need to tweak it slightly - Linux will crash and burn if you specify more memory than available.

Solution 2:

Install Mode was set to "on" in the BIOS. Either I changed it inadvertently or it defaulted when I installed a new hard disk. Changed this back and it is seeing all the RAM.