new installed memory not recognized

I've searched for a while, but I couldn't find the answer to this
problem. I have a Dell Inspiron 8500. I decided recently that I
wanted to upgrade my RAM. I originally had 2x256 MB, so I decided to
buy a 1 GB card from Dell. Dell's site said that the maximum memory
that I could have was 2 GB, so I'm not exceeding the maximum memory.

Anyway, I took out one of my 256 MB cards and replaced it with the 1
GB card. I've looked at the Bios and it now says that I have 1280 MB
of memory installed, so it looks like the hardware is recognizing the
new memory. However, when I get into Windows XP SP2, I right click
"My Computer" and click "Properties" and the
system says that I have only 508 MB of RAM. Then if I click
Ctrl+Alt+Del and look under the performance tab, it says that my
physical memory is only 519726 KB. So it looks like Windows XP is
still only recognizing 512 MB of RAM and not 1280 MB.

I have no clue what to do. I've tried switching slots between the 1
GB and 256 MB cards and got the same result. I've also updated my
Bios to the newest version and have just tried using only the 1 GB
card. When I do that, the Bios says 1024 MB of RAM, but Windows XP
still says the same thing. Can anybody help me with this problem? I
just don't understand why Windows XP can't recognize the increase in
RAM. Thanks so much!

mystical32 wrote:
> I've searched for a while, but I couldn't find the answer to this
> problem. I have a Dell Inspiron 8500. I decided recently that I
> wanted to upgrade my RAM. I originally had 2x256 MB, so I decided to
> buy a 1 GB card from Dell. Dell's site said that the maximum memory
> that I could have was 2 GB, so I'm not exceeding the maximum memory.
>
> Anyway, I took out one of my 256 MB cards and replaced it with the 1
> GB card. I've looked at the Bios and it now says that I have 1280 MB
> of memory installed, so it looks like the hardware is recognizing the
> new memory. However, when I get into Windows XP SP2, I right click
> "My Computer" and click "Properties" and the
> system says that I have only 508 MB of RAM. Then if I click
> Ctrl+Alt+Del and look under the performance tab, it says that my
> physical memory is only 519726 KB. So it looks like Windows XP is
> still only recognizing 512 MB of RAM and not 1280 MB.
>
> I have no clue what to do. I've tried switching slots between the 1
> GB and 256 MB cards and got the same result. I've also updated my
> Bios to the newest version and have just tried using only the 1 GB
> card. When I do that, the Bios says 1024 MB of RAM, but Windows XP
> still says the same thing. Can anybody help me with this problem? I
> just don't understand why Windows XP can't recognize the increase in
> RAM. Thanks so much!
>

Crucial (who I trust explicitly) advises 1GB per slot, max 2GB of PC2700
DDR. http://www.crucial.com/store/listpar...on+8500+Series

So, I'm thinking that if your RAM is correctly specified, you perhaps
have disabled PnP Operating System in BIOS (I do not know if your BIOS
even has this setting), you need to confirm the RAM in BIOS, or have
disabled the PnP service in WinXP.

You might run the Crucial System Scanner bot to see if it suggests
anything special about your computer. Everest might also be informative
about what you have in the computer.

Q