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bveagle7Flag for United States of America

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Windows7 doesn't recognize all the installed memory neither does the bios (only 1 of 2 512MB)

Windows 7 doesn't recognize alll the 1GB installed memory. The Bios and the computer shows only 512MB.

The system information report shows 512mb RAM and 1.44GB of virtual memory.

In my previous operationg Windows XP Pro system, the computer and bios would show all the 1 GB RAm installed.

Is this normal and do I have to do anything to get a better performance?
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Andrew Hancock (VMware vExpert PRO / EE Fellow/British Beekeeper)
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if the BIOS only shows 512MB, the operating system will show the same.

I would suggest try reseating the RAM modules.

Do you have two 512MB modules, try switching them round, it's possible one has become faulty.
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Yes I have two 512MB modules and I switch them around and it always sees only the same one. Before switching to Windows 7 my winXP Pro would recognize both 512 MB.

The systeminformation report gives me 512 MB of RAM but shows 1.44GB Virtual Memory?
If the BIOS only sees 512MB ram, the OS will not see anymore!

512MB physical detected
1.44GB Virtual Memory includes the pagefile (virtual memory is in the page file)

Try reset the computer BIOS to defaults? (maybe remove the CMOS battery)

Do you have a graphics card which is sharing computer memory?
I do not have a graphic card that uses the memory.

Can you have 512MB of RAM and also 1GB of Virtual Memory?

Physical Memory + Pagefile size (pagefile is virtual memory, swap file on disk, when you run out of memory, it swaps it to disk, this is called virtual memory).

are you sure you've got two 512MB modules, and not two 256MB, what happens when you just install one?
I have two 512MB modules and they would both show on winXP but when I switched to Wiin7 I can see only one and it's always the same one whether I move it from one slot to the other.

If the Computer BIOS shows 512MB, some is wrong with the hardware and not the OS.

Memory, Configuration of computer.

If you only install one memory module, how much memory is installed?
OK I uninstalled one of the modules and it gives me the same results.

When I installed the other module by itself, the computer would not start so I looked at the module and it is a PC3200 and the other module is PC2700 so I suppose that Win7 will not let the PC3200 module work.

I remember thta it was showing two modules and 1GB in WinXP.
what, it still only show 512MB?

It's the motherboard that's not compatible with PC3200.

Reset BIOS and check the SPD timings of the RAM in the BIOS settings.
I checked the motherboard specs and it supports oonly PC2100/PC2700.

WinXP used the 1GB but win7 will not.

So let's forget about it. I will go and buy a one GB PC2700 memory module.

Thanks for helping.

The problem is solved

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if the BIOS doesn't recognise the total memory in the machine, it's the wrong memory.

does not matter what operating system is installed.

"It's the motherboard that's not compatible with PC3200."
don't forget it worked with XP ok..
I downloaded the memtest86+ but could not find the way to use it so I gave up and will buy new memory.

Thanks for the sugestion.
bveagle - if you have problems, post them here, i'll guide you
what exactly did you download? the ubcd i posted is an ISO file, and has to be burned as an iso to cd, not just copied !