1282MB hardware reserved memory - seems too much to me..

Well, I've read soooo much about this problem, I'm already got confused.
As the title mention - I think I've got too much of my phisycal memory allocated to hardware by Win 7. (Ultimate 32 bit edition, BTW).
Yes, I know there's many posts with this prbolem - but that part of my problem too...:)
I read some articles, and I thought I understand my problem, and than - I read more, and more, and more... the more that I've read - the less I can determine where the problem come from.
I read this, and this, and this and this so far, and that why I got all confused up.

So, let's start from scratch - I've got a desktop : (specs)
AMD Athlon II X2 245 processor, 2900 Mhz.
MOBO - Gigabyte GA-MA785GM-US2H - Link here.
2 kits of RAM, 2GB each.

When I open System Properties - It shows in the RAM section - 4.00 GB installed - 2.75 Usable.
Why is this?
I've got an onboard video card (ATI Redeon HD 4200), but it takes only 512MB of the memory. Where's the rest of it?



Here is image from Resource Monitor, showing that 1282 MB is hardware reserved memory.

IMPORTANT: I've got into this problem because I've just installed 2GB memory stick, in addition to the 2GB memroy stick I've already got. I've checked with CPU-Z and they match. Installed them as a dual channel, on the blue DIMMs on my MOBO.

I'll be pleased if someone can sort out the mess in my head about all those memory problem..

Thanks in advance.

well i see the problem is because of softwares installed in your system.
do these steps:
1) go to msconfig (type it in start menu) then uncheck any unwanted programs that are running in your startup. place the screen shot of that here so i can help you on that.
2) check your drivers and make sure you have the latest and updated ones
3)check your system with an antivirus

my phisycal memory allocated to hardware by Win 7. (Ultimate 32 bit edition, BTW).

If it's a 32bit system = (approx) 3gb limit, your numbers looks perfectly normal IMO (AlterUrEgo example seems to be 64bit).
Snip from my ultimate 32 4gb laptop, hp\amd\ati.

Cheetah64d

What is the model of the RAM that you are using... and how you installed them on your motherboard..

mmkarimi said:

well i see the problem is because of softwares installed in your system.
do these steps:
1) go to msconfig (type it in start menu) then uncheck any unwanted programs that are running in your startup. place the screen shot of that here so i can help you on that.
2) check your drivers and make sure you have the latest and updated ones
3)check your system with an antivirus

How do you know it's a software problem, while it's stated in the Resource Manager as Hardware reserved?
Anyway,
1) Did it. no help.
2) drivers of what? I think everyting is up-to-date in my computer.
3) I have Avira AV in my computer, no viruses according to it.

4wd said:

my phisycal memory allocated to hardware by Win 7. (Ultimate 32 bit edition, BTW).

If it's a 32bit system = (approx) 3gb limit, your numbers looks perfectly normal IMO (AlterUrEgo example seems to be 64bit).
Snip from my ultimate 32 4gb laptop, hp\amd\ati.

I don't think that in 32bit there's 3gb limit. more like 3.7 or so. anyway - I will be really glad to find out there's no problem and this is the standart situation. Somehow I got the feeling it's not.. maybe you also have a problem.. start think about that..

centaur78 said:

Cheetah64d

What is the model of the RAM that you are using... and how you installed them on your motherboard..

I attached screenshots of CPU-Z so you can find out. One wierd thing - I bought the second RAM according to the CPU-Z data about the first one. However - when it came - I was suprise to find out that its height size is about half of the first. Still, same numbers as the first according to CPU-Z, as you can see for yourself from the attached photos..

okay; these physical memories are being in used with software installed in your system. when your os is on, each one take some space in your RAM, physical memory to load up its environment, even win7 takes some space for its visualization.
do as follow, run task manager and sort your memory, find out what programs are consuming more memory, and terminate them if they are unnecessary, also please place your msconfig-->startup screen shot and your task manager sorted by memory here, so i can help you better on that..

Cheetah64d said:

mmkarimi said:

well i see the problem is because of softwares installed in your system.
do these steps:
1) go to msconfig (type it in start menu) then uncheck any unwanted programs that are running in your startup. place the screen shot of that here so i can help you on that.
2) check your drivers and make sure you have the latest and updated ones
3)check your system with an antivirus

How do you know it's a software problem, while it's stated in the Resource Manager as Hardware reserved?
Anyway,
1) Did it. no help.
2) drivers of what? I think everyting is up-to-date in my computer.
3) I have Avira AV in my computer, no viruses according to it.

4wd said:

If it's a 32bit system = (approx) 3gb limit, your numbers looks perfectly normal IMO (AlterUrEgo example seems to be 64bit).
Snip from my ultimate 32 4gb laptop, hp\amd\ati.

I don't think that in 32bit there's 3gb limit. more like 3.7 or so. anyway - I will be really glad to find out there's no problem and this is the standart situation. Somehow I got the feeling it's not.. maybe you also have a problem.. start think about that..

centaur78 said:

Cheetah64d

What is the model of the RAM that you are using... and how you installed them on your motherboard..

I attached screenshots of CPU-Z so you can find out. One wierd thing - I bought the second RAM according to the CPU-Z data about the first one. However - when it came - I was suprise to find out that its height size is about half of the first. Still, same numbers as the first according to CPU-Z, as you can see for yourself from the attached photos..

Cheetah64d ...

Your RAM's are installed in unganged ie. in single channel mode... and not Dual channel mode as you mentioned in the first post... Check the DC mode under the memory tab of CPU Z...

in order to set it to Dual you need to put the RAM's as mentioned below..

Install them in DDR2_1 & DDR2_2



once done .. Go to bios and under MB intelligent Tweaker (MIT) > DCTs Mode... set it to ganged

Save and start your system... Check and tell me what you find

Cheetah64d

Did you change the bios option as i mentioned before ????

Go to bios and under MB intelligent Tweaker (MIT) > DCTs Mode... set it to ganged

And yes i still believe what i said was right... Its not the matter of performance or stability but i think you need to understand what Dual or single channel means or Ganged or Unganged means... and yes they are related..and no people don't make names up just for their happiness ... there is a reason why the channels are colour coded and why they are named that way...

First what AMD says about ganged and unganged mode..

AMD has some excellent documentations that can be download for free. Let's examine some extract of the “BIOS and Kernel Developer’s Guide (BKDG) For AMD Family 10h Processors ”. On section 2.8 we can find some considerations on ganged vs unganged mode. If you are interested in checking the doc, I suggest you to especially read these sections:
2.8 - DRAM Controllers (DCTs)
2.8.5 - Ganged or Unganged Mode Considerations
2.8.8 - DRAM Data Burst Mapping
2.12.2 - DRAM Considerations for ECC

In short, the documentation indicates that:

In ganged mode, we have a 128 bit wide logical DIMM that map the first 64 bit on physical DDR channel A and the last 64 bit on DDR channel B. So we can state that a single 128 bit operation is effectively split between two memory channel; on the other hand, the DCTs can not operate independently. In other words, the physical address space is interleaved between the two DIMM in 64 bit steps

In unganged mode, each DCT can act independently and has its own 64 bit wide address space. In this mode the processor can be programmed to interleave the single, physical address space on the two normalized address space associated with the two memory channel; however, the finer possible interleaving unit is the cache line size (64 bytes)

The image below should help explaining the differences between ganged and unganged modes:



As you can see, in the ganged mode the physical address space is spread between the two memory channel with a 64 bit granularity: this means that two consecutive 64 bit access will read from two different memory channels and, more importantly, that a 128 bit access can utilize both channel.

On the other hand, in the unganged mode a (relatively) large portion of physical address space is bound to a single memory channel. In the graph above this portion is 64 bytes length, but the K10 processors can be programmed to use an even more coarse grained interleaving scheme. However, the normal interleaving unit in unganged mode is 64 byte length (as shown in the graph), as longer unit can cause a tangible performance loss.

From what we see, one should think that neither approach is the ideal one: the usual registers and operands size is 64 bit (8 byte), so it appear that both the ganged and unganged methods will read this 64 bit entity over only a single memory channel, effectively wasting bandwidth. A byte interleaved (or bit interleaved) mode should give as a great performance boost, right? Simply stated: no. The key point to understand here is that processors do not move in and out from memory data chunks of arbitrary length, but use a fixed-sized scheme: they move data from and to main memory only on a cache line base. On Phenom processor the cache line size is 64 byte long, so these processors move data from and to main memory only in 64 bytes chunks. This means that if we try to read a byte at address 0x0, the entire cache line (64 byte) will be fetched by the processor! While this can seems counterproductive, it has its reasons, especially related to space locality and cache design. It is beyond the scope of this article to explain why processors behave in this manner, but in short we can state that this design permit good performance boost (because exploit code and data space locality) and the creation of very dense caches.

As memory operations happens in 64 bytes chunks, it appear that ganged mode will always win: it can spread that 64 bytes operations on the two memory channel, while the unganged mode will only use a single memory channel. The reality, however, is the the unganged mode rarely suffer from this problem, because normally there are many outstanding memory request to be completed, so there are many outstanding cache line to be fetched from or stored to main memory. While the ganged mode will be faster in operating on a single cache line, the unganged mode can theoretically operate on two cache line at a given moment (with some restrictions). This parallelism can be realized because the memory controller incorporate an 8 entry depth memory controller queue (the “MCQ” box in the drawing above), for a total of 8 outstanding cache line requests.

However, simply stating that the unganged mode has the potential to be often on par with the ganged mode is not enough: in this case, we can simply use the ganged mode and forget about the unganged mode. The point is that the unganged mode has potential to be faster that ganged mode. Why? Because we must realize that main memory access don't happen immediately, as the DRAM chip require many ns to be accessed: after this initial access time the data can be transferred quite quickly, but the initial access steps can be very slow (from a processor standpoint). Starting two memory operations at the same time, the memory controller has the possibility to hide at least partially the latency involved in the setup steps of the second operations. Obviously this is not always true, but it is a possibility indeed and, so, this can be an advantage of unganged vs ganged method. Moreover, using the unganged mode the memory controller can theoretically both write to and read from memory at the same time: this should help memory copy routines and multitasking operating system, where many processes can both read from and write to memory at the same time.

Summarizing the whole point, we can state that:

• the ganged mode has the potential to be faster than unganged mode because it use a more fine grained interleave mode
• the unganged mode has the potential to be faster than ganged mode because it can start two memory operations at the sime time, effectively hiding at least part of the latency involved in the second operation. Also, this mode permit to both read from and write to memory at the same time, with the intrinsic advantages that this possibility implies.

And this is gigabytes FAQ on why its shows as unganged and dual....

GIGABYTE - Support & Downloads - FAQ