Debian does Not detect additional RAM

Abhid · 09-10-2012, 11:13 AM

Hi friends. I've recently installed Debian Squeeze 2.6.32.5-686-bigmem

I have a 256 MB RAM installed in one slot, and 1 GB in the other. But despite that, the system refuses to recognize the 1 GB RAM and shows only the 256 MB component.

SHould anything other than bigmem kernel installation be done ?

TobiSGD · 09-10-2012, 11:30 AM

Which mainboard do you use? If it is an older one, can it handle 1GB modules? If it can, does the BIOS show the additional RAM?

Abhid · 09-11-2012, 06:24 AM

I use a 2006 model Lenovo PC (never really seen the internals thoroughly).

I've been trying to figure out from where exactly in the BIOS do we see the RAM ? I delved into all the options, sub-options but didn't seem to find it.

brianL · 09-11-2012, 06:53 AM

I don't think you need the bigmem kernel for RAM less than 4 GB on a 32-bit system.

Abhid · 09-11-2012, 07:15 AM

In that case, what could be the reason for the RAM not getting detected ? My total RAM is just 1 GB + 256 MB in both slots

Three months back, I (unsuccessfully) installed a Debain Squeeze with KDE 4. It wouldn't boot normally, so I used to boot using a LiveCD. The LiveCD did show all the RAM.

Now I tried for a couple of months to fix it, but without success. So, I took a backup of all my data and freshly re-installed Debian Squeeze just a few days back. But now it doesn't detect all the RAM.

TobiSGD · 09-11-2012, 07:46 AM

Please post the output of

Code:

cat /proc/meminfo
free -m

Abhid · 09-11-2012, 10:21 AM

Output of cat /proc/meminfo

Code:

rooty@rooty:~$ cat /proc/meminfo
MemTotal:         221772 kB
MemFree:            3780 kB
Buffers:            4636 kB
Cached:            82472 kB
SwapCached:         8244 kB
Active:            97940 kB
Inactive:         100960 kB
Active(anon):      55652 kB
Inactive(anon):    60616 kB
Active(file):      42288 kB
Inactive(file):    40344 kB
Unevictable:           4 kB
Mlocked:               4 kB
HighTotal:             0 kB
HighFree:              0 kB
LowTotal:         221772 kB
LowFree:            3780 kB
SwapTotal:        433144 kB
SwapFree:         388516 kB
Dirty:               268 kB
Writeback:             0 kB
AnonPages:        108164 kB
Mapped:            51644 kB
Shmem:              4432 kB
Slab:               9396 kB
SReclaimable:       4120 kB
SUnreclaim:         5276 kB
KernelStack:        1680 kB
PageTables:         3696 kB
NFS_Unstable:          0 kB
Bounce:                0 kB
WritebackTmp:          0 kB
CommitLimit:      544028 kB
Committed_AS:     508400 kB
VmallocTotal:     803000 kB
VmallocUsed:        4044 kB
VmallocChunk:     792604 kB
HardwareCorrupted:     0 kB
HugePages_Total:       0
HugePages_Free:        0
HugePages_Rsvd:        0
HugePages_Surp:        0
Hugepagesize:       2048 kB
DirectMap4k:        8000 kB
DirectMap2M:      221184 kB

Output of free -m

Code:

rooty@rooty:~$ free -m
             total       used       free     shared    buffers     cached
Mem:           216        207          8          0          4         81
-/+ buffers/cache:        121         95
Swap:          422         43        379

273 · 09-11-2012, 10:32 AM

When you boot the machine it often tells you how much memory you have installed as part of the Power On Sell Test. If you go into BIOS there might be an option like "show POST" or "show long boot messages" and that ought to tell you how much RAM the BIOS sees.
have you tried booting with just the 1GB stick in your first slot? It could be you have a faulty slot or something odd like the motherboard only accepting RAM of equal capacity. If it doesn't work with just the 1GB stick in the first slot then it is worth googling your motherboard manual to check the maximum module size.

Abhid · 09-11-2012, 12:28 PM

My desktop can support upto 4 GB RAM. The specifications are as follows :

Code:

Lenovo 3000 H Desktop PC Features
Intel Pentium 4 Processor 517 with HT Technology
(2.93 GHz, 533 MHz, 1-MB L2 cache)
Intel Graphics Media Accelerator 950
Intel 945G Express
256MB (upto 4.0GB) RAM – DDR2 533MHz (PC2-4200)
40-GB SATA 4,200 rpm hard drive
CD-RW Optical Drive

I've cross checked most of these values with the Linux commands.

My earlier Debian version (before getting ruined) did report 1.2 GB RAM. That is when I switched from XFCE to KDE in the first place, else it wouldn't have run.

In the BIOS, I modified the value of show long boot, but I can't see any difference. I mean the large LENOVO Logo comes, after which there is a CMOS error screen (this has been ever since I installed Linux). I press F1 after which the Grub menu pop-up comes.

business_kid · 09-12-2012, 05:51 AM

I've had something like this in the past. It was the ram. The issue was that my board was too old for the ram purchased (pc100m/b vs pc133 ram) and there were more address lines and fewer pages on the new ram. My m/b couldn't tweak the top address line, so I ended up with half the ram available.

A p4 is 32 bit, right? The max adressing space for them was ~3.2G, iirc. This is all off top of head but might be worth checking, that's all.

TobiSGD · 09-12-2012, 05:58 AM

Quote:

Originally Posted by business_kid

A p4 is 32 bit, right? The max adressing space for them was ~3.2G, iirc. This is all off top of head but might be worth checking, that's all.

The P4 517 in this machine is 64 bit, FWIW.

Abhid · 09-12-2012, 09:25 AM

OK I see the RAM in the BIOS now after the settings. Its indeed 256 MB.

But I can swaer Linux reported 1.2 GB RAM in the earlier "Lenny" configuration. How elese did I run KDE for so many months after removing XFCE ?

Do I have to update the BIOS ? If so, how ?

273 · 09-12-2012, 09:33 AM

As I mentioned it may be a faulty RAM slot, or the motherboard may want pairs of modules to be the same. Either way, try with just the 1GB stick in the first slot and you'll soon find out whether it works or not.
Edit: Or just start by reseating the 1GB module, in case it wasn't in the slot properly when fitted.

johnsfine · 09-12-2012, 09:54 AM

Quote:

Originally Posted by 273

try with just the 1GB stick in the first slot and you'll soon find out whether it works or not.

"first" (from the BIOS's point of view, which is what matters) may not be at all obvious when you look at the slots on the motherboard.

We don't know whether it is something fixable by re seating (dirty contacts, not inserted well in the first place, or vibrated out of position over time). Or isn't compatible with the choice of slot (by undocumented rules of that BIOS) or incompatible with being used together with the other stick (either at all or as a function of relative physical position). Or isn't compatible at all. Or is a defective memory stick.

So I agree with your basic approach. Re seat it and try it alone (without the smaller capacity memory stick). I have no opinion on which of those two things you should try first. But when trying it alone, if it doesn't work in one slot, try it once in each slot (don't know how many you have). Don't try it just in the first slot.

If/when it works alone, experiment with whether it works together with the other stick.

273 · 09-12-2012, 10:02 AM

Quote:

Originally Posted by johnsfine

"first" (from the BIOS's point of view, which is what matters) may not be at all obvious when you look at the slots on the motherboard.

"First" may have been the wrong choice of words -- I meant the one the working 256MB stick is in as we know that slot works and that it's the one the motherboard can "see". If it's not the first then the motherboard doesn't care which slot is used (I can never recall how common it is for them to care).