RAM problem!!

[Magpie]

4GB Ram Sticks 2x 2gb but in control panel its only saying 3gb useable!!!

that 25% boost in ram lose would really help me

Been trying to fix this all night but cant do notting! could anyone help?

http://i1241.photobucket.com/albums/gg515/magpie1304/Ram.png
Aspire M1610
http://support.acer.com/acerpanam/ [...] 0sp2.shtml

Motherboard: acer 672m01-1.1-8ksh
CPU: Geforce 8800 GS
RAM: 4GB 800mzs
Processor: intel 2 duo core E4600
BIOS: Phoenix Award Standard Settings R01-B1
OS: Windows 7 Ultimate x64

Never had a problem before, but i upgraded my Ram from 2gb to 4gb and i was using 32bit..
tryed upgrading to win 64 bit,

tryed this,

Check the advanced boot options.
1. Go to Start, in the search bar type msconfig and press enter.
2. System Configuration window will open on the screen.
3. Click on tab named "boot".
4. Click on "Advanced Options" and uncheck the box for "Maximum Memory".

looking in my bios and theres notting for memory mapping, ticked the 14-15 memory hole thing

tryed swapping sticks around and reseated but notting works!


any help would be great

[Rbstr]

Specifications:

Supports: Skt 775 Intel® Core™2 Duo processor (with up to 800 MHz FSB)
Intel® Pentium® Dual-Core processor
Intel® Pentium® D processor
Intel® Pentium® 4 processor
Intel® Celeron® D processor
Intel® Celeron® processor
Supports: Up to 4 GB of DDR2 400/533/667 MHz SDRAM
Chipset: SIS 672 + 968
So, there may be that.

But who knows.

[Duskguy]

what ram are you using, is it compatible? i.e. DDR2 400/533/667 MHz SDRAM?

im not an expert with PCs, but couldnt it also be the OS using some of the ram, and therefore only leaving 3 gigs? a gig for the OS seems a lot to me, but as i said, im no expert and it was just an idea.

[Bags]

Dusk my pc lists 8170 mb of ram even if ~1gb or so is used up upon boot.

[Mutant]

I suspect your problem lies in your motherboard only supporting 32 bit addressing some of those addresses are used to map the memory from PCI-E ect.. so windows can not use all 4GB.


Some motherbords support more than 32 bit addressing and use a feature called memory mapping, this enables a 32bit windows OS to use all 4GB of ram.
Most of today's consumer motherboards support 32GB of ram with 35bit memory addresses, (if you installed 32GB in those motherboards windows would see ~31GB of usable ram) but some cheaper/slightly older ones use 33bit addressing and come across the same problem you are seeing when 8GB is installed.

http://static.duartes.org/img/blogPosts/memoryLayout.png

"How does the limit work?
Physical memory addresses are divided into two sections: the PCI memory address range (also known as Memory Mapped I/O), and the RAM available to the operating system. This explains why even with 4 GB of memory, available RAM is less than 4 GB.

PCI memory address space is used to transfer data by the BIOS, I/O cards, networking, PCI hubs, bus bridges, PCI Express, and graphics cards. It starts at the top of memory at 4 GB and takes memory addressing to lower address ranges. PCI Express alone takes up 256 MB of address space, and each
component also requires an additional amount. Therefore, it is very easy for a system with 4 GB of physical memory to lose 512 MB or more address space before any RAM addressing is allocated.

RAM addressing starts at 0 MB and takes memory addresses to higher address ranges up to the bottom of the PCI memory address space, which is around 3 to 3.4 GB. The bottom of PCI memory address space may fall outside of this range depending on system configuration, especially if more than one graphics card is installed."

http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c00667512/c00667512.pdf

http://support.microsoft.com/kb/978610

http://duartes.org/gustavo/blog/post/motherboard-chipsets-memory-map