RAM usage in Windows 7 64 bit

Upgraded to Windows7 64 bit from Vista 32 bit. Added RAM to 5GB (reason
I upgraded to 64 bit was to get around the 3GB 32 bit limitation.) Now
system shows 5GB but only 3.3GB available for use. Task manager shows
5.12GB installed, 3.326GB available or cached and 1.794GB "hardware
reserved"(?). Is this 1.794 not available for software? If not, how to
make it available for software?

I really wanted the performance improvement of 64 bit and increased RAM.
How do I get Windows7 64 bit to utilize the full 5 GB?

System is HP running 64 capable 2.13 hz dual core Intel.

Whatever it is it's something you would be better off asking HP, or
reading up on the specs of your computer. It could be a BIOS setting,
reserved memory for a plug-in card (especially video RAM), etc.

Did you do a clean install of Win 7 x64?

It's not a clear cut answer not knowing exactly what your hardware is.
Some systems have limited memory capability by design. I have a Dell
1501 laptop with 4GB DDR2 installed. Win 7 tells me only 2.25GB of the
4GB is available for the system. That's something Dell designed into
the system. The 2.25GB limitation doesn't cause me any problem though
since I have a SSD and installed a RAMDisk and now have a virtual drive.

There should a setting in your BIOS for address redirection or offset (it's
called different things in different BIOSs.) What it does is move the
various hardware reserved memory addresses up out of the 4 GB boundary,
allowing you to fully utilize your RAM. Otherwise, you end up with the
memory addresses that your RAM would use being taken up with things like
your network card, your video card, etc.

I'm having the same problem with my copy of windows 7 64-bit. I've got 4GB
of ram installed but windows says only 3 is usable. My motherboard is a
Biostar PT880 Pro-A7 but I can't find the bios setting you described. Any
help would be greatly appreciated.

Sorry, no familiarity with Biostar mobos or their BIOS.

It also depends on exactly which version of the board you have. There
are 3 editions of the PT880 Pro-A7 and the specs for 2 of them is only
2GB of RAM is supported. Now, even though they say only 2GB is
supported you may realize a bit more than that but not all 4GB. Dell
says my 1501 laptop only supports 2GB. With 4GB in the laptop Dell has
it configured so that Win 7 only sees 2.25GB.

Then your best bet is to contact Biostar Support and ask them why you
only get 3GB RAM with Win 7.

Are you sure you have the Windows 7 x64 version installed?

I am definitely running 64 bits. Did a clean install and it shows it is
running 64 bits. Board is ASUS Tek Leonite 5.00 and the bios is Phoenix
Tech LTD 5.09. The computer is an HP Media Center with 2.13 GHz Intel
Core 2 HP-Pavilion RT680AA-ABA m7747c.

Sounds like it is a BIOS limitation. I see no option in Bios to change
anything related to this.

The motherboard manual says max ram is 4GB.

Then you need to find the setting in Memory for a "Memory Hole" and
change the setting.

It was already set to "disable" setting to "enable" did nothing of note

In our similar thread about this issue in alt.windows7.general, another user
is reporting a similar problem with his Sony computer, which reports 4.0 GB
RAM, 3.84 Usable. His screenshot shows that, yes, he is running 64-bit
Win7. I posted a similar screenshot there showing no such limit in my Win7
x64 with 4 GB on board.

So far as I have ever read or heard, Win7 imposes no such RAM limitation.
As you said, the limitation must be in the BIOS - or the mobo or somewhere
other than in Win7 itself.

Some boards with integrated graphic adapters do share the memory, which
results in exact that difference for the RAM.
This usually can be adjusted in the BIOS. However, lowering this too
much does not leave enough memory for the graphic chip. For W7 128MB
should be a minimum.

Excuse me good people. The writer states that he upgraded from a 32 bit
operating system to 64 bit system on the same machine. In this operation,
one must fully understand the design concept of the manufacturer. The 32 bit
operating system was supported by a 32 bit bios. That being said, you can't
get 64 bit performance from a 32 bit tree. All configurations will remain in
the 32 bit realm. That being said, change the bios from 32 bit to 64 bit.
Contact the manufacturer and ask for a 64 bit image of the bios. Understand
that the hardware installed in the machine may have driver issues when going
from 32 bit to 64 bit. The operating system should fix this if drivers are
available. This should fix your problem forever. Your only limitation in ram
upgrade will be bios and physical machine profiles.

Please find me just one link to any motherboard manufacturer that lists
a 64-bit BIOS.

There are NONE! There is no such thing in the wild!

The BIOS in ROM has nothing to do with the bitness of the OS. Vista and Win
7
don't use the ROM for anything. It's totally replaced by 64-bit software
after
IPL. The ROM is only used to load the first part of the OS which then loads
the
rest of the OS. ROM calls haven't been used since Win ME. Soon there won't
even be a ROM BIOS. It is being replaced by EFI. In any case, ROM BIOS is
a
16-bit program, not 32-bit.

There wouldn't be a problem with your RAM being reported properly. I just
want to know the trick to getting it to run Windows 7 on just 6megs of RAM

Agreed. Many BIOS's do have a setting to enable more than 4GB ram. The
setting might be called Enable Memory Mapping, or whatever other label the
motherboard mfg might have applied. That should only be enabled when running
a 64-bit os. It re-maps peripheral ram addresses out of the way so all
installed ram can be used.

[infamous_otter]

haha, gues what this is a known issue by microsoft and a very common issue with windows 7. I am having the same issue, upgrade from vista (wich read all 6 gigs of my ram) to win 7 64bit wich sees all 6 gigs but but only considers 3.5 gigs usuable. Yup thats right Windows 7 64 Bit sometimes just cant get past that 3.5 gig memory limit.

After spending a week dealing with microsoft tech support on the phone they considerd this issue unresolved and claim the are currently working on an update to fix it.

according to the tech guy from microsoft, it is an issue with the bios and the motherboard. all of you that are having this problem, it is becuase something in windows 7 does not fully support either your mother board or your bios or both. The memory mapping will do you no good. Unless you go out and buy the most latest motherboard, processor and ram, you are going to continue to have this issue. <-- Directly from microsoft tech support.

To the guy that posted this "It also depends on exactly which version of the board you have. There
are 3 editions of the PT880 Pro-A7 and the specs for 2 of them is only
2GB of RAM is supported. Now, even though they say only 2GB is
supported you may realize a bit more than that but not all 4GB. Dell
says my 1501 laptop only supports 2GB. With 4GB in the laptop Dell has
it configured so that Win 7 only sees 2.25GB."

Gues what? They lied to you. Their hardware is not fully compatible with windows 7. That is why it only sees 2.25 gb.

So... since I have installed windows 7 64 bit, I have lost over half of my ram (3.5gigs Unusable), I have lost the ability to print on any of the 20 printers at my home and office (there are as of yet no drivers for windows 7 64 bit on most printers), oh yeah, and the latest windows update killed microsoft office.

Check out this screen shot of windows 7 64bit not passing the 3.5 gig memory limit
EPIC FAIL!!!

I want my money back.

I have a Dell Studio XPS 435MT from September 2009 and Windows 7 (64 Bits)
installed.
The latest available BIOS is installed (Version 1.1.3)
This computer reports 6 Mb memory from the installed 6 Mb memory.
So what's the problem ??

mine runs just GREAT on 4g of ram.

[omicronpersey]

I had such problem: Windows7 64 bit showed what 4Gb RAM installed but 3Gb usadge. Bios showed all 4Gb of RAM. The next solution treats this problem:
1. If BIOS does't show all installed memory then enable MEMORY REMAP function.
2. If BIOS show all installed memory then check
a) MSCONFIG.EXE-->Boot-->Advanced options: disable checkbox maximum
memory (if checkbox disable yet then enable it, reboot system and after
that disable again (i know what it looks like "magic" but it work!)
b) Reboot computer and upgrade performance raiting.

PS: Sorry for my English and best wishes from Russia.

I have Win7 64-bit and 8Gb of RAM installed; Win7 sees it all just fine.

Yeah - this works!! I went from 2 to 5.1GB RAM usable (out of 6GB).... the no. of cores checkbox should also be unticked...