OS limitation when installing memory

  Ssylvester 17:11 28 Jan 2014

Hi i bought a PC last year in december. the specs are: motherboard M5A78L-M/USB3, Ram Hyperam (2x4) 8GB DDR3 1600, processor amd fx 4100 quad core 3.6ghz, graphics card NVidia GeForce GT640-2GD3 - Asus edition, 500gb hard drive, 64-bit operating system windows ultimate... I have noticed that only 4 gb of my ram is installed on my motherbored as i have 2x4gb inside my pc system and looked at a lot of things why it wasnt installed as im not an expert with my pc... i went onto looking at my motherboard and saw this in the specifications- * Due to OS limitation, when installing total memory of 4GB capacity or more, Windows® 32-bit operation system may only recognize less than 3GB. Install a 64-bit Windows® OS when you want to install 4GB or more memory on the motherboard. click here only think this means due to my operating system my motherbored is limited to a certain amount of ram, i dont know how to fix it or if it is fix able any advice or help very appreciated, thanks.


  Bris 17:31 28 Jan 2014

Its the OS that limits the amount of memory you can install.

A 32 bit OS can only address a little over 3GB of memory, you can install more but the OS cant use it.

A 64 bit OS can address as much memory as you motherboard can take.

  larchwoodmark 17:33 28 Jan 2014

hi, have you checked in computer properties, that the o/s is 64bit


  Ssylvester 18:00 28 Jan 2014

my motherboard is apparently capable for 32gb of ram ddr3 but im not a clue how operating systems work to be honest, so will i need to change my operating system and if i do would you recommend any if this is the case, and yes it says 64-bit operating system and when i turn it on it opens with windows 7 ultimate

  Ian in Northampton 18:07 28 Jan 2014

I think you may be confused.

Your motherboard can accept - you can install - a certain amount of memory. With most boards, there are four slots for memory. So, if you bought 4GB 'sticks' of memory, you could install a total of 16GB.

However, your PC was very probably supplied with less than the maximum possible memory installed. That's very common.

If you have a 32-bit operating system - XP, Vista or Windows 7 - it can only 'address' a little more than 3GB of memory, so there's no poit in installing any more than that.

A 64-bit version of those operating systems, though, can address significantly more than 3GB - more than your motherboard could support, and more than you'll ever need.

From what you say, it sounds as if you have a 64-bit version of Windows. Therefore, it could be worthwhile to install additional memory modules on your motherboard. You don't need to change anything to do this.

  Fruit Bat /\0/\ 18:08 28 Jan 2014

If you are running g4bit windows 7 ultimate it should see all the RAM

I have noticed that only 4 Gb of my ram is installed on my motherbored as i have 2x4gb inside my pc system

Where have you seen this? Are both memory sticks physically inserted in the motherboard?

  Bris 18:18 28 Jan 2014

Go into CONTROL PANEL>SYSTEM and that will tell you how much RAM is installed.

If its 4GB then if two modules are installed you will have 2 x 2GB memory modules.

If you want to increase this you can either add a new pair (if you have 4 slots) or remove the existing modules and replace them with larger modules such as 2 x 4GB

  Ssylvester 18:26 28 Jan 2014

yes i have 4 slots and was planning to eventually upgrading to 4x4gb im probably going to sound stupid saying this as i am confused i thought you had to just put the ram sticks in the motherboard to install them or do i need to update anything? and fruit bat i bought mine with 8 gb already inside just recently i went on my computer properties then was curious why it said only 4 gb was installed, my brother has 16 gb and said that on his laptop so i thought what the hell... i eventually went on a website with specs of my motherboard and saw that, didn't understand it and came here and i have tried plunging them out and in and different slots by the way thanks for the help guys...

  Bris 18:58 28 Jan 2014

You arent stupid for asking a question thats what the forums for so dont worry.

A couple of things come to mind firstly you bought the PC with 8GB but did you get 8GB?

Secondly modules are usually installed in alternate slots not side by side.

If you remove one of the modules what do you get 4GB or 2GB showing in system?

  alanrwood 20:34 28 Jan 2014

FDirstly it is essential to determine which version of Windows you have installed, 32 or 64 bit. Go to Control Panel and double click on "System". A scren with "basic system Information" will appear. This should tell you whether you have a 32 or 64 bit version installed and how much memory is being recognised by Windows as installed and usable.. Please let us have this info and it may then be possible to give a definitive answer to your question.

  Bris 20:55 28 Jan 2014

Download CPU-Z and run it, its free.

Click on the memory tab and this will tell you the total memory size.

Click on the SPD tab and this will give you the size of the module in slot 1.

Click on the down arrow by slot one and choose slot 2 and this will tell you the size of the module in slot 2.

Repeat for slots 3 & 4.

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