Solved Hardware reserved Memory?

[bala2289]

I had 2 gb of ddr3 ram installed before, yesterday i added 2 more gb but the system uses only 3.24 gb and the rest is reserved for hardware. I hope it is used for graphics memory but i have an external graphic card of 1 gb video memory. How to release this memory. I have searched many forums and they suggested to uncheck the maxmemory in msconfig, that didnt work.

Also they asked to enable memory remapping in bios, but my bios doesnt have that option. My OS is windows 7 ultimate 32 bit.

I'm attaching the screenshots below.

 

[Maguscreed]

There are a lot of things that can cause this. However since you are on 32 bit windows 3.2 gigs is the maximum it will make use of. This is a limitation in the 32bit system not an actual error per say.

 

[bala2289]

thanks for the reply, so no way for using the remaining 750mb ram . I have another question.. hope you saw the screen shots i attached it shows that i have 6+ gb of virtual memory. Is it really necessary to have such huge space since i've already have 3.2 GB of ram..

 

[StalkeR]

It's because you're using 32bit OS. I have the same as you when was using 32 bit, but now I don't.

 

[sygnus21]

Have a look at this and note the "Hardware Reserved" section.... Investigate memory usage with Windows 7 Resource Monitor | TechRepublic

Typically, the amount of Hardware Reserved memory ranges from 10MB to 70MB but can vary depending on the system’s hardware configuration and might be several hundred MB.

You might also want to see these posts....

- http://www.sevenforums.com/performa...al-memory-but-1-74-gb-usable.html#post1649304

- http://www.sevenforums.com/performa...-memory-but-1-74-gb-usable-4.html#post1650067

 

[murmatron]

The memory is not hardware reserved. 32-bit Windows 7 deliberately prevents you from using it even if PAE is enabled.

To demonstrate this as fact...

1) Download and install Gavotte Ramdisk 1.0.4096.5
2) Create a PAE ramdisk
3) Use ramdisk
4) Point proven

On my 4GB 32bit system Gavotte Ramdisk is able to use 990MB of supposedly 'hardware reserved' RAM. This is a fact - not something that I read somewhere.

If you're willing to forego the use of hibernate or hybrid-sleep (sleep works fine and I have a UPS so I don't care) then you can create an additional page file on the ram disk which Windows will prefer due to the fact that it will likely be at least 20 times faster than your HDD.

How to use full 4GB RAM in Windows 7 32 Bit (Gavotte RAMDisk in Windows 7) | Homepage of Jens Scheffler

 

[whs]

The fact that you can only use 3.2GBs is not a RAM problem per se but an address space problem. A 32bit system has only 4GB-1 of address space and everything has to fit into there. And that also includes a graphics card with its own RAM. It has to be addressed somehow.

Here is a bit more about all the other stuff that needs address space: Maximum Memory in 32-bit Windows Vista : Windows Vista and Windows 7 Help

 

[Corazon]

You're right on one point: none of the memory is actually reserved for anything. What is reserved is a portion of the 32-bit address space just below the 4GB barrier. (You can't address more than 4GB with just 32 bits, it's numerically impossible.)

Where it gets tricky is that modern motherboards actually have at least a 36-bit address bus (from what I understand) - the 4 additional bits would allow access to 16 blocks of 4GB each for a total address space of 64GB. This is where PAE (physical address extension) comes in, using exactly these extra bits to allow a 32-bit Windows system to access memory that was mapped above 4GB (which is possible and even normal even if only 4GB of physical RAM is actually installed).

Using PAE, however, Windows could access memory that was remapped by the BIOS to reside in an address space above 4GB. The reason it won't is because far too many 32-bit device drivers were developed under the assumption that there'll never be any memory addresses beyond 4GB of RAM available, and if these drivers suddenly had to deal with memory addresses above 4GB they'd crash and burn, bringing the system down with it.

So Microsoft had to implement this classic 3.xx GB limitation in all 32-bit versions of Windows, so that no address space above the 4GB barrier is visible to anything running on the system.

That is, unless something explicitly requests access to the "invisible" memory, which is what Gavotte Ramdisk does.

So, the reason Windows only uses 3.25GB out of 4GB is because only 3.25GB are mapped within the address space below 4GB. The rest is mapped above 4GB up to 4.75GB, while the address space between 3.25GB and 4GB is mapped to all PCI devices and motherboard resources so they can exchange data with the system through that address space. This is the only way to ensure 32-bit drivers will work correctly, by not exposing them to the >4GB address space. Thus the artificial limitation.

But using PAE, Windows is able to allow Gavotte Ramdisk to access the >4GB memory and use it for the RAM disk.

 

[sygnus21]

The memory is not hardware reserved. 32-bit Windows 7 deliberately prevents you from using it even if PAE is enabled.

So, it is therefore... hardware preserved. The fact that you can use a 3rd party program to get around it doesn't negate the fact that "Windows 7 deliberately prevents you from using it even if PAE is enabled"

I'm just reporting what's stated here - Investigate memory usage with Windows 7 Resource Monitor | TechRepublic

And here - Windows 7 memory usage: What's the best way to measure? | ZDNet

Anyway I'm not going to call myself a memory expert so....

And yes WHS, it is a address space thing.

 

[murmatron]

Edit: Snipped, misread last sentence as a question

The memory is not hardware reserved. 32-bit Windows 7 deliberately prevents you from using it even if PAE is enabled.

So, it is therefore... hardware preserved. The fact that you can use a 3rd party program to get around it doesn't negate the fact that "Windows 7 deliberately prevents you from using it even if PAE is enabled"

...

And yes WHS, it is a address space thing.

The RAM between 3.25GB and 4GB is absolutely not hardware reserved; it's remapped (as Corazon stated) to above 4GB so that the devices in the machine can be accessed through memory-mapped I/O in the region below 4GB. The remapping is necessary because the PCI-Express bus still only has 32bit address lines and can't address memory above 4GB. This is true even in 64bit Windows, Linux or whatever - it's not done by the operating system.

By contrast, every processor since the Pentium-I-can't-remember-which-one-exactly has been capable of 36bit PAE addressing (that's 64GB)

The claim that allowing PAE addressing in Windows causes (or caused at some point in the past) problems with some drivers may well be true for drivers that are not written following the Windows DDK specification, with the 'gotcha' being that realistically, there's no way to tell in advance of them crashing your system. For that reason I more-or-less accept Microsoft's stated rationale for hobbling PAE on desktop Windows since XP-SP3, but the fact remains that there exists a way to use this memory in a way that makes badly written drivers irrelevant, so I often feel the need to point this out.

It's interesting to note that Gavotte Ramdisk is based on a sample ramdisk program provided by Microsoft in the Windows DDK a long time ago.

 

[Corazon]

It does make you wonder why Microsoft doesn't just enable the extra memory in 32-bit Windows for special usages - a default RAM disk, supplemental pagefile.sys for the current session or just a place to use for Superfetch/Readyboost caching instead of regular main memory.

Then again, with the ongoing 64-bit crusade this is becoming less and less relevant anyway.

Interesting point in case: I actually use a RAM disk on my laptop with 4GB RAM in the invisible memory. Windows only sees 2.75GB because the onboard video takes a 256MB chunk from 2.75GB to 3GB for itself. Only a few MB above 3GB is actually wasted to map PCI address space, so I'm able to use nearly a full gigabyte for the RAM disk.

(I've since discovered that the laptop's BIOS maps the fourth GB of RAM to an address space from 4096MB to 5120MB, leaving a 1GB hole between 3072MB and 4096MB. Crazy!)

I've arranged for pagefile.sys to live exclusively in that RAM disk so I don't need one on the HD, saving me extra space - and in terms of security, it's the ultimate solution since the pagefile is zapped into nothingness with every reboot.

 

[bala2289]

Thanks guys... I dont want to waste my 750 mb unused so im going to install Gavotte Ramdisk...
One more doubt guys.. my video card has 1 gb of memory and even if the hardware reserved memory is added to it. It should be some 1700 mb but my dxdiag says it has 2417 mb, where did the remaining memory come from and will it be utilized entirely by the applications?

 

[stormy13]

This is what that is,

http://www.sevenforums.com/tutorials/89278-video-memory-virtualization-brief-guide.html

 

[Corazon]

The card doesn't map its memory into the PCI address space all at once. The claim that you'll lose whatever onboard RAM the card has is a myth.

It does map its onboard memory through a much smaller window to transfer data to and from the CPU/system RAM. Portions of the videocard's onboard memory are dynamically mapped in and out as needed through that window.

As for the 2417MB shown in DXDiag, that's the amount of shared system memory your card can use if its own onboard memory fills up completely (1GB onboard plus ~1417MB system RAM), but Windows has the last word on that. Don't worry, it doesn't mean the card actually keeps 1417MB of your RAM from being usable.

 

[bala2289]

Thanks a lot stormy,murmatron and corazon..

 

[bala2289]

lol Ramdisk uses 16 mb of missing memory... what happen to the rest??

Guys sorry for asking so dumb questions..
I notice that the pagefile's used size changes from time to time even when a lot of the system's ram is free, y this that?
I thought that the page file will be used when the ram runs out.. So y use it when u have enough ram?

 

[whs]

Why don't you just leave it as is. There is no reasonable way to make use of the 750MBs with a x86 system. If you want to use that total RAM, you will have to get a x64 system. If you keep playing around with it, you will just ruin your system.

 

[bala2289]

Why don't you just leave it as is. There is no reasonable way to make use of the 750MBs with a x86 system. If you want to use that total RAM, you will have to get a x64 system. If you keep playing around with it, you will just ruin your system.

My system is x64 capable but noway i'm going to reinstall all the applications to use 64 bit os.

 

[whs]

My system is x64 capable

That does not mean anything if you are running a 32bit OS. And if you do not want to install a 64bit system, you will have to live with the 3.25GBs of used RAM. In daily life there is not really such a difference to using 4GBs - you would probably not notice any real difference.

Have a look in Resource Monitor > Memory tab. The colored bar will tell you how much RAM is being used. And remember, the dark blue portion is for caching only and is "available" RAM.

 

[Maguscreed]

Why is this thread still going on?
I mean seriously it was solved in the first two responses.
The rest of this really seems like meaningless bickering to me.
I'm sorry guys but this is really unlike most of you.