RAM (installed vs total, 64 bit Windows 7)

[JGU1956]

I have a question about the amount of effective RAM working in my desktop (PC) computer.  I recently installed 2 additional 4GB modules of DDR3 RAM to my machine.  It previously had 8GB, so after the upgrade it should now have 16 GB helping me churn out masterpieces  .

Sorry the description below is long.  If this question has been covered elsewhere please feel free to just respond with links and say "go do some reading".

I am running Windows 7 Business Edition, 64 bit.  The mother board is an Asus P7P55D-E LX.  The processor is an Intel i7 quad core running at 2.93 GHz.

The issue is whether or not the 8GB which I've just installed is actually working.  Although my feeling is that certain things are running faster, I am still unsure because:
1.   Windows (via msconfig\System Configuration\Boot tab\BOOT Advanced Options) sometimes says it has a bit over 16 GB (which would be right) but on other occasions it says nil or 4 GB.
2.   Windows (via Control Panel\System) also says there are 16GB installed RAM, but only 8 GB usable.  (The 8GB discrepancy might correspond with the newly installed but somehow non-functional RAM).
3.   Windows (via Task Manager\Performance tab) says the total physical memory is 8190 MB (ie about 8GB) and available memory is about 5770 GB which would presumably be after graphics and other services/programs have taken their share.  (Again, where is my new RAM?!)
4.   The utility Auslogics BoostSpeed 5.1.0.0 says that the machine has "total" 16GB which should be right.
5.   In another feature of the Auslogics utility it shows the actual usage of memory as a steady 2.07 GB out of a total of 16GB, regardless of whether LR (or any other major application) is running.  It also states that the machine has 16 GB of virtual memory and ("but only?") 8 GB of physical memory.
6.   Lightroom 4.0 (Help\System Info) says that built in memory is (only) 8190 MB (let's say 8GB).  In the next line it shows real memory used by LR as something which fluctuates, understandably, according to what I'm looking at or doing in LR, but this variability seems to be at odds with the unvarying RAM usage displayed in Auslogics and described in point 5 above.

The BIOS shows that memory remapping is enabled, which I take to mean that if new memory is added (as I've just done) the machine will automatically recognise it, recalculate what is available and start using it when required.

I understand from looking around the internet on other sites that a graphics card (which I have) typically takes about 1GB of memory, and other services and programs running would probably also reduce the 'available" memory, but surely that would not account for 8 GB going AWOL.  And if I'm running a 64 bit OS I shouldn't have a problem using more RAM than 4 GB (which is the 32 bit OS's ceiling).

Can anyone tell me what's going on?  Last night after installing the new memory, I thought I had discovered my inner geek.  Tonight I feel like just another punter!

Thanks in advance,
John.

[Justan]

Hi,

To test for installed RAM, check your system’s BIOS. Go into the BIOS settings menu. This is typically accessed during POST. This will tell you the physical RAM installed.

To test for RAM that Windows can recognize do the following:

Click on the start button.
Type “taskmgr” but without the quotation marks and then press the Enter key.

Windows Task manager will start.
Go to the tab labeled Performance.
Check out the numbers on the bottom left.
You will see a section that references “Physical Memory (MB).
The total field represents the amount of total physical memory available to Windows.

Often after installing RAM memory, it is necessary to increase the amount of virtual memory that the system uses.

To do this, go to Start, then Control Panel, then System.
Once in System, click on Advanced System Settings.
Once in Advanced System Settings click on the tab labeled Performance Options.
Once in the Performance Options display, click on Advanced.
Once in Advanced Click on the button labeled Change… under the virtual memory heading.

Here you will find the amount of virtual memory that is configured. Virtual memory is a contiguous block of drive space that is reserved for use by Windows. Note that virtual memory is also known as a page or paging file. Typically the size will be “System managed” but in any event, note the bottom section, under the heading “total paging file size for all drives. Make sure that the recommended amount is the minimum amount allocated. In addition, if your computer has more than one drive, make sure that the drive that DOES NOT have the operating system on it, is the drive used for virtual memory. Typically, but not always, using a 2nd or other drive for the page file will increase performance.

In any event, the drive that you use for the page file should not be an otherwise heavily used drive.

As a hint, if you just got yourself a ultra-fast SSD drive, use this drive for the virtual memory drive, even if it has the OS installed on it.

Note that if you make any changes here you will probably have to restart the computer for the changes to take effect.


 

[JonathanRimmel]

This may be a simple question, but did you check to see if your RAM was compatible with your motherboard? Is the the right type, speed, # of pins, etc?

[John.Murray]

I see a lot of confusion regarding this - here's a useful article describing the various memory usage fields in Windows Task Manager:

http://support.microsoft.com/kb/2160852

Scroll down to "Monitoring RAM and virtual memory usage"

Setting your Page File size is important and can also be confusing - setting it to 125% of total physical RAM is a good rule of thumb, but may not be optimal in all cases.  

http://support.microsoft.com/kb/889654

As far as PageFile location, if your boot is an SSD your good!  If, however you are using magnetic media, I'd recommend you defrag the PageFile if possible:

http://live.sysinternals.com - look for pagedfrg.exe

Finally, if you *do* have an SSD for boot and are worried about space - be aware that Windows 7 creates a hibernation file (Hiberfil.sys) thats equal in size to the amount of RAM installed.  You can turn this off (but read the warnings regarding sleep modes):

http://support.microsoft.com/kb/920730

[Steve Weldon]

After you think you have your BIOS set up.. also turn on the ability to read the post messages, like how much RAM is recognized by the system BIOS.  If you're not seeing 16gb here, then Windows won't see it either.

This is important because often if your memory settings or CPU settings are wrong, especially if you're trying to over clock or do anything other than the default frequency.. you'll find that the wrong settings will result in less RAM showing up in post.  If this is happening, start with your default, save and reboot, and verify all 16gb is now showing.  Then change your settings carefully, save and reboot, and verify again.  Often this is where the ball is dropped, someone sets in what they think they want with the Bclk, multiplier, or memory profile.. and never notice their 12gb is now 8gb or their 16gb is now 12gb..

Only after the above is verified do you worry about what's in Windows.  You can simply right click on "Computer" in your start menu, choose "'properties" and you'll get the basic information screen for your computer.. and it should show all 16gb of RAM under "installed memory (RAM)." 


After ALL the above is done.. THEN go into the task manager and worry over how it's distributed.

[Rhossydd]

I recently installed 2 additional 4GB modules of DDR3 RAM to my machine.

Another issue is if the additional modules are matching the pre-installed ones. Modern systems are incredibly fussy about this, even revision changes of the same module may not work together properly.
Ideally you want all the ram modules to be exactly the same; manufacturer, size, speed and revision number. The only reliable way to do this is buy everything in one purchase from your supplier, buy the new lot, then sell on the old.

[dreed]

...
3.   Windows (via Task Manager\Performance tab) says the total physical memory is 8190 MB (ie about 8GB) and available memory is about 5770 GB which would presumably be after graphics and other services/programs have taken their share.  (Again, where is my new RAM?!)
...
The BIOS shows that memory remapping is enabled, which I take to mean that if new memory is added (as I've just done) the machine will automatically recognise it, recalculate what is available and start using it when required.
...

The only number that is of significance here is what Task Manager says - 8GB.

As others have mentioned, you need to disable "Quiet" boot in the BIOS or enable the display of POST messages to see how much RAM the BIOS thinks you have.

To start with, you should reset your BIOS to its defaults.

To verify that your new RAM actually works, remove all the RAM from your system and put the new RAM into the two light blue slots. If the system doesn't boot up with 8GB of RAM then one of the two new sticks is faulty.

If it does boot up, try then adding the old sticks to the empty slots (both dark coloured.)

[JGU1956]

Thank you one and all for your advice.

The critical point was (as several of you have said) that the BIOS was showing that the system was not recognising the new RAM.  How Windows interprets the situation comes later- you have to get the BIOS doing/saying the right thing first.

The solution was that someone suggested that I simply swap the RAM modules to different slots.  Instead of old/new/old/new I slotted them in in the order old/old/new/new (in other words Corsair/Corsair/Kingston/Kingston).  That fixed it.

It went some way to demystifying the inner workings of a computer for me  .  Next time, installing an SSD!

Thanks again,
John.

[Edalongthepacific]

My book: http://www.amazon.com/Building-Your-High-Performance-Computer-ebook/dp/B005WKHHDG
has a large section about memory modules and memory compatibility. I also think it is very reasonably priced and downloadable as an ebook. One of the things I stress about memory is that the modules should have identical timing characteristics. Timing is, basically, relates to BIOS settings and how the CPU and other chips communicate with the memory modules. Voltage, needless to say, is also critical. If at all possible, buy a memory "Kit" with memory that your motherboard manufacturer has listed on their approved list or consult motherboard technical support.

[Phil Indeblanc]

It also will take out RAM in the amount of Video ram your video card has.

[Farmer]

It also will take out RAM in the amount of Video ram your video card has.

Nope, not with 64bit Windows.