# Installed RAM Not Being Fully Used in Windows 7 64-bit



## conrad1on (Jul 14, 2007)

*OS:* Windows 7 Home Premium 64-bit
*Processor:* Intel Pentium 4 CPU 3.06 GHz
*Motherboard:* Gigabyte (Fujitsu-Siemens) GA-8I915PM Revision 2.0
*RAM:* 4 DDR 1 GB sticks

After Googling around on this for longer than I care to think about, I thought that I might as well just ask for help directly, while hopefully providing as much useful information as I can.

When I bought my computer about five years ago, it came with *1 GB* of RAM (two *512 MB* sticks). At some point, I added an extra two *1 GB* sticks to give a total of *3 GB* of memory.

Recently, I decided to upgrade my computer's memory again in preparation for installing the full version of Windows 7, so I swapped the old pair of *512 MB* sticks for another *1 GB* pair so that I had *4 GB*, which is apparently the maximum for my motherboard.

I noticed that despite having *4 GB* of RAM installed, only *3.25 GB* seemed to be used, however I thought this was just a limitation of the 32-bit version of the Windows 7 Release Candidate I was using, and the problem would rectify itself when I installed the full 64-bit version of Windows 7.

Well, having just installed the 64-bit Windows 7, I'm still apparently only getting *3.25 GB*'s worth of my installed *4 GB*, and I'm at a loss as to how to remedy it.

I'm aware that there are countless similar - or indeed identical - examples of this issue all over the Web, however none of the answers I've seen so far have been much help to me.

The most common suggestions seem to be:

*1) Enable Memory Mapping in the BIOS*

Unfortunately, no such option exists in my BIOS (*Award Software version 10Q*). I even managed to upgrade it, but it didn't add any new menu options.

*2) Make sure 'Maximum Memory' is unchecked in msconfig under Advanced options in the Boot tab*

It already is unchecked, given that this is a new clean install and I hadn't been mucking about with it.

Currently, in the _basic information_ window in the _Control Panel_, my _Installed memory_ is listed as *4.00 GB (3.25 GB usable)*. In the _Resource Monitor_, which gives more detail on how the RAM is shared out, _Hardware Reserved_ is marked at *769 MB*, which looks suspiciously like the missing chunk. I don't know if this was also the case when I was using the Release Candidate, as I never bothered checking.

A number of people have suggested that this is perfectly normal, that Windows 7 will deliberately hold back a certain amount of RAM for hardware like graphics cards. As an experiment though, I took out two *1 GB* sticks of RAM and put the old *512 MB* pair back in to take the memory back down to *3 GB*, and when I had a look in _Resource Monitor_ after booting up, it showed only a negligible amount (*1 MB*) of memory marked as _Hardware Reserved_.

Curiously, the BIOS only lists about *3328 MB* of RAM as being available, despite Windows itself recognising the full *4 GB*, even though it doesn't seem to want to use it all for some reason.

So, I suppose what I'm essentially asking is, am I stuck with this situation, and have I wasted £50 on, effectively, an extra *250 MB* of RAM?

I'd quite like to get a definitive answer either way before I plough on and start reinstalling everything properly. Thanks in advance.


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## Tyree (May 10, 2009)

OEM Mobo's have very few user adjustable Bios settings. A Bios update "might" help but I wouldn't do it just to see .75GB of RAM that you will probably never use.


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## conrad1on (Jul 14, 2007)

Yeah, it was more about the wasting money thing though. Thanks anyway.


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## Wrench97 (May 10, 2008)

While I'm not all that familiar with Fujitsu-Siemens PC's HP's from the same vintage do have a motherboard limitation of 3.2gig it almost seems as though they were only meant to use 32bit os's and at the time the manufacturers where not concerned making sure address space above that was available.

If your Bios is only listing 3328 as available then it is not a Windows configuration issue it's a Bios/hardware issue or most likely limitation.


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## conrad1on (Jul 14, 2007)

Hmm... Well, I just wish I knew either way really.

I should say that I recently replaced the motherboard, and despite the new one being ostensibly the same model, it had a different brand name (Fujitsu-Siemens - the original was Packard Bell) and a different type of BIOS.

I don't know if the previous Sunshine BIOS had an option for memory remapping, but I'll kick myself if it did.


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## Wrench97 (May 10, 2008)

OEM motherboards rarely have the extra features like memory mapping that a retail board does, even though in this example the board is manufactured by Gigabyte it was made to F/S specs and F/S supplied the Bios which is limited to cut warranty(no overclocking burnouts) and Support(limited options means less remote troubleshooting time) costs.
The OEM boards often have half the power control circuits and take a limited list of CPU's as an example to cut manufacturing costs.


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## smneufell (Apr 20, 2010)

I didnt read in detail the other posts or look up the mb, so this is a quick suggestion. Could the missing memory be for an integrated video card or one that shares memory?


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## conrad1on (Jul 14, 2007)

I don't think so, as when I used just 3 GB instead of the full 4 GB of RAM, it seemed to be completely utilised, as none of it was reserved or marked as 'unusable' or whatever.


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## FreoHeaveho (Aug 22, 2006)

According to your motherboard's manual it supports up to 4gb. That motherboard should be able to use the full 4GB with a 64bit OS. I have 6GB installed on my Win 7 system and i use over 4GB frequently when mounting images and such. 

I would suggest searching for a bios update. Also, I would reset the CMOS if i were you. That can sometimes help.


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## conrad1on (Jul 14, 2007)

Unfortunately finding an update for my motherboard's BIOS has been tricky, particularly since the BIOS provider, Award Software, has been swallowed up by Phoenix Technologies. The Phoenix site itself seems to require some kind of subscription just to update the BIOS, which is not something I'm keen to do.

As I said, I did manage to update it with the most recent version I could find, but I didn't get any new options as a result. I might give the CMOS thing a go though.


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## conrad1on (Jul 14, 2007)

Tried resetting the CMOS by removing the battery for a few minutes then booting up, but it seems to have made no difference.


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## Wrench97 (May 10, 2008)

Some of those OEM boards will not make all the ram available to the OS it's reserved for add in cards and motherboard functions, they were designed and the bios written for a 32 bit OS so there was no need to make more available.


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