Missing RAM, 8190MB not 8192MB

[Lifeofgold]

I know this sounds petty when put next to people missing half of their RAM, but it is perplexing me.

System in question:

ASUS P5N-B rev 1.02
BIOS REV 1401 (Last update released)
Intel Core 2 Duo E8400
8 GB OCZ Gold PC6400 RAM (4 matching modules 2GB each, sequential S/Ns)
Windows 7 64 Bit Ultimate

The BIOS shows 8192 MB of installed memory and shows 8191 MB usable,also Windows shows 8190 MB usable. When I do some simple math looking at the KB available in Windows Task Manager, it appears that 1489 KB of RAM is missing. the RAM is NOT overclocked. I have used MEMTest86+ to test the RAM. I tested all the RAM at once, and I tested each module individually. I tried to move the RAM around; one modules at a time and "Musical Modules". On each try, whether it was one module, or some combination of modules , the BIOS showed 1 MB of RAM missing. This RAM does not show this when placed in a different system. Due to the fact that I only see one MB missing regardless of the number of modules installed, I can only surmise it has to be the motherboard. So I ask, "What is ASUS doing with that RAM? If someone knows, please shout out. I know it seems minor, but it is very annoying and I can't stop thinking about it. I thank you for your time.

 

[ronintexas]

http://www.howtogeek.com/131632/hardware-upgrade-why-windows-cant-see-all-your-ram/

Also check this:
1) Click Start > Run
2) type "msconfig"
3) Go under the "boot" tab
4) click "advanced options" button
5) UNCHECK! "Maximum memory"
6) Reboot

 

[Pinhedd]

I know this sounds petty when put next to people missing half of their RAM, but it is perplexing me.

System in question:

ASUS P5N-B rev 1.02
BIOS REV 1401 (Last update released)
Intel Core 2 Duo E8400
8 GB OCZ Gold PC6400 RAM (4 matching modules 2GB each, sequential S/Ns)
Windows 7 64 Bit Ultimate

The BIOS shows 8192 MB of installed memory and shows 8191 MB usable,also Windows shows 8190 MB usable. When I do some simple math looking at the KB available in Windows Task Manager, it appears that 1489 KB of RAM is missing. the RAM is NOT overclocked. I have used MEMTest86+ to test the RAM. I tested all the RAM at once, and I tested each module individually. I tried to move the RAM around; one modules at a time and "Musical Modules". On each try, whether it was one module, or some combination of modules , the BIOS showed 1 MB of RAM missing. This RAM does not show this when placed in a different system. Due to the fact that I only see one MB missing regardless of the number of modules installed, I can only surmise it has to be the motherboard. So I ask, "What is ASUS doing with that RAM? If someone knows, please shout out. I know it seems minor, but it is very annoying and I can't stop thinking about it. I thank you for your time.

This is perfectly normal. Several megabytes of memory are reserved for firmware usage.

The lower 1MiB of physical memory is reserved for firmware usage. The hardware abstraction layer and kernel will make use of some of it, but the kernel will not attempt to manage this region of memory at all. This is why you're seeing 8192MiB installed but only 8191MiB usable.

There may also be an ISA memory hole at 15MiB-16MiB. There's no need for this hole on modern computers, but it can still be found at times. Although the ISA hole can often be disabled, it usually cannot be remapped if it is enabled.

The much, much larger PCI hole cannot be disabled, but it can be remapped on most chipsets.

 

[Lifeofgold]

Thank you, NOW I can sleep. (haha) When I had this RAM on a different MB, I did not see any RAM missing and I had thought I may have hurt it in the switch. Since OCZ went bye-bye, and I will not buy more DDR2 RAM, I am glad it is not faulty. I never considered about my add-in cards as a factor but it makes sense. ASUS puts their money into quality, but everyone need to cut a corner somewhere so they nibble from the installed RAM for firmware info on things like add-in cards. I can accept that. Now to ponder on that missing sock...........

 

[Pinhedd]

Thank you, NOW I can sleep. (haha) When I had this RAM on a different MB, I did not see any RAM missing and I had thought I may have hurt it in the switch. Since OCZ went bye-bye, and I will not buy more DDR2 RAM, I am glad it is not faulty. I never considered about my add-in cards as a factor but it makes sense. ASUS puts their money into quality, but everyone need to cut a corner somewhere so they nibble from the installed RAM for firmware info on things like add-in cards. I can accept that. Now to ponder on that missing sock...........

Intel is responsible for that, not Asus.