Windows 7: RAM issue

Coolness · 30 Jan 2010

hey, I have 4gb of RAM, 3gb usable, in a 64-bit OS. Probably just another n00b question, but hey, thats what the forum is for. So, why am i missing a Gig?

noobvious · 30 Jan 2010

Quote: Originally Posted by Coolness

hey, I have 4gb of RAM, 3gb usable, in a 64-bit OS. Probably just another n00b question, but hey, thats what the forum is for. So, why am i missing a Gig?

My guess is the highlighted portion of the snip......the other GB is being used by your graphics card.

Datalyss · 30 Jan 2010

I also have 4Gb installed, but Windows is only recognizing 3.44GB. Why is this?

bobkn · 30 Jan 2010

Quote: Originally Posted by Datalyss

I also have 4Gb installed, but Windows is only recognizing 3.44GB. Why is this?

The standard response: desktop versions of 32 bit Windows (including 7) can address 4GB at most. However, some of these addresses are reserved for other purposes, so that a 32 bit system with 4GB of RAM will always show less than that available. The exact amount will depend on what hardware devices are present.

There are 32 bit server OSes that support PAE (physical address extension) that support more. They don't support 64 bit applications, though, so the limits on individual applications remain.

pparks1 · 30 Jan 2010

Quote: Originally Posted by Datalyss

I also have 4Gb installed, but Windows is only recognizing 3.44GB. Why is this?

Most likely because
1). you are running a 32-bit version of the operating system
2). you have an integrated video card which is sharing system RAM.

whs · 30 Jan 2010

For a 32bit system it is a problem of address space. As was said, graphics (even if they have their own memory) and some other functions need address space which can range from 0.5 to 1.2GBs. Thus the adddress space available for the RAM that the OS uses is between 2.8 and 3.5GB.

For 64bit systems there is no address space problem because the 64bit Windows 7 address space goes up to 128GBs. It is, however, possible that an integrated graphics uses "shared memory" which takes real RAM away from the OS. For the size of that you have to check the specs of the on-board graphics chip.

Coolness · 31 Jan 2010

Quote: Originally Posted by whs

For a 32bit system it is a problem of address space. As was said, graphics (even if they have their own memory) and some other functions need address space which can range from 0.5 to 1.2GBs. Thus the adddress space available for the RAM that the OS uses is between 2.8 and 3.5GB.

For 64bit systems there is no address space problem because the 64bit Windows 7 address space goes up to 128GBs. It is, however, possible that an integrated graphics uses "shared memory" which takes real RAM away from the OS. For the size of that you have to check the specs of the on-board graphics chip.

My graphics card has 1gb DEDCATED memory, and has nothing to do with system RAM. The OS is 64-bit, and when i had 3gigs (just upgraded) It showed 3 gigs, not 2 gigs. So, whats wrong?

stormy13 · 31 Jan 2010

Does the bios report 3 or 4 GB?

Have a look in the bios for anything to do with memory hole or memory remapping, and if available make sure it is set to enabled (being an Acer, it may not be there).

whs · 31 Jan 2010

Quote:

My graphics card has 1gb DEDCATED memory

See, that's a bit of information you did not give us before. Would have saved me a lot of typing.

stormy13 · 31 Jan 2010

Quote: Originally Posted by whs

Quote:

My graphics card has 1gb DEDCATED memory

See, that's a bit of information you did not give us before. Would have saved me a lot of typing.

And doesn't make any difference on a 64 bit OS. If that was the case mine would be showing 4 GB installed and 3.5 GB available.

Windows 7: RAM issue

RAM issue problems?