[Solved] Missing RAM?

[WhatUsernameIsFree?]

Hi all,

I think I'm missing some RAM somewhere. A DuckDuckGo shows that I should need a 64bit OS to ensure I can use it all.

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             total       used       free     shared    buffers     cached
Mem:          3651        961       2689          0         65        340
-/+ buffers/cache:        555       3096
Swap:            0          0          0

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# dmidecode 2.11
SMBIOS 2.3 present.

Handle 0x1000, DMI type 16, 15 bytes
Physical Memory Array
	Location: System Board Or Motherboard
	Use: System Memory
	Error Correction Type: None
	Maximum Capacity: 1 GB
	Error Information Handle: Not Provided
	Number Of Devices: 4

Handle 0x1100, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x1000
	Error Information Handle: Not Provided
	Total Width: 64 bits
	Data Width: 64 bits
	Size: 2048 MB
	Form Factor: DIMM
	Set: None
	Locator: DIMM_1
	Bank Locator: Not Specified
	Type: DDR
	Type Detail: Synchronous
	Speed: 533 MHz
	Manufacturer: 7F98000000000000
	Serial Number: 3D36AA26
	Asset Tag: Not Specified
	Part Number:                   

Handle 0x1101, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x1000
	Error Information Handle: Not Provided
	Total Width: 64 bits
	Data Width: 64 bits
	Size: 2048 MB
	Form Factor: DIMM
	Set: None
	Locator: DIMM_3
	Bank Locator: Not Specified
	Type: DDR
	Type Detail: Synchronous
	Speed: 533 MHz
	Manufacturer: 7F7F7F7F7F9B0000
	Serial Number: 00000000
	Asset Tag: Not Specified
	Part Number: CT25664AA667.M16FJ

Handle 0x1102, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x1000
	Error Information Handle: Not Provided
	Total Width: 64 bits
	Data Width: 64 bits
	Size: 2048 MB
	Form Factor: DIMM
	Set: None
	Locator: DIMM_2
	Bank Locator: Not Specified
	Type: DDR
	Type Detail: Synchronous
	Speed: 533 MHz
	Manufacturer: 7F98000000000000
	Serial Number: 3F36A626
	Asset Tag: Not Specified
	Part Number:                   

Handle 0x1103, DMI type 17, 27 bytes
Memory Device
	Array Handle: 0x1000
	Error Information Handle: Not Provided
	Total Width: 64 bits
	Data Width: 64 bits
	Size: 2048 MB
	Form Factor: DIMM
	Set: None
	Locator: DIMM_4
	Bank Locator: Not Specified
	Type: DDR
	Type Detail: Synchronous
	Speed: 533 MHz
	Manufacturer: 7F7F7F7F7F9B0000
	Serial Number: 00000000
	Asset Tag: Not Specified
	Part Number: CT25664AA667.M16FJ

BIOS shows:


Thanks for any ideas or help.

[xenopeek]

And surprise us, did you install the 32 bit or the 64 bit version of LMDE? You basically answered your own question With 8 GiB RAM I'd normally recommend you to install LMDE 64 bit. But, should you have the 32 bit version you can install the PAE kernel and this will allow you to address up to 64 GiB on your 32 bit install--though each individual process is still limited to a 4 GiB address space (should not be a problem for you, unless you do professional media creation like movie editing or rendering, in which case you should go with the 64 bit version anyway as that is faster for those kind of tasks).

To install the PAE kernel, run:

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sudo apt-get update
sudo apt-get install linux-image-686 linux-headers-686-pae

After reboot you will have 8 GiB RAM available in Linux.

Edit: if it wasn't clear, the default kernel on LMDE 32 bit can address up to 4 GiB RAM and no more. It also only uses one CPU core. On a modern system (generally multi-core CPU) really you should go for a 64 bit install by default IMHO; the 32 bit is for older computers (think 1990) and the default kernel ensures LMDE will run on that kind of hardware. That said, installing the PAE kernel will solve both of these shortcomings for you.

[WhatUsernameIsFree?]

Oops,

Major thing to miss out on information wise. I think it's 64bit (bigger number than 32bit, means it's better, right?) Should I still install those headers?

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uname -a
Linux desktop 3.2.0-3-amd64 #1 SMP Thu Jun 28 09:07:26 UTC 2012 x86_64 GNU/Linux

[xenopeek]

No, then don't install those packages unless you have 32 bit (and you have indeed 64 bit). Something else is wrong. Basically, the first part of the dmidecode is saying that your motherboard supports RAM chips of maximum 1 GiB capacity, and you install 2 GiB RAM chips. So only half of the memory of each RAM chip is addressable, as your motherboard can't handle more.

Handle 0x1000, DMI type 16, 15 bytes
Physical Memory Array
Location: System Board Or Motherboard
Use: System Memory
Error Correction Type: None
Maximum Capacity: 1 GB
Error Information Handle: Not Provided
Number Of Devices: 4

Before we jump to that horrible conclusion though (you having bought RAM chips too big), which motherboard do you have or what is the make & model of your computer? Let's confirm it with the specs of the manufacturer.

[WhatUsernameIsFree?]

Hi,

It's a Dell Dimension 5100. Not sure how I tell which motherboard it has? This company says I can have 8GB max.
Thanks

[xenopeek]

Dell 5100 service manual, from Dell: http://support.dell.com/support/edocs/s ... specs1.htm. I'll quote the relevant bit:

Memory
Type = 400-MHz and 533-MHz DDR2 unbuffered SDRAM
Memory connectors = four
Memory capacities = 256 MB, 512 MB, or 1 GB non-ECC
Maximum memory = 4 GB

So I'm sorry to say, but it appears the largest SDRAM chips the Dell 5100 supports are the 1 GiB kind. For a total of 4 GiB RAM installable.

I hope you can get a full refund on your current SDRAM chips, as even if you remove two of these I suspect you would then only be able to address 2 x 1 GiB RAM instead of the 2 x 2 GiB RAM installed. Of course, you can leave these chips in if you can't get a refund and you can use 4 GiB of the installed RAM as you are currently doing (the free command shows a little less, probably because part of the 4 GiB is used by your graphics card).

[WhatUsernameIsFree?]

I'll try get a refund, but unfortunately I think it's a case of "it's been opened and used, no refunds".

At least that answers the question.

Thank you very much for your help

[WhatUsernameIsFree?]

For what it's worth, I've removed two of the 'blocks' of RAM and free shows me:

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free -m
             total       used       free     shared    buffers     cached
Mem:          3651        755       2895          0         65        318
-/+ buffers/cache:        371       3279
Swap:            0          0          0