Windows XP Zapped by Memory

I bought new memory (256 MB SDRAM) for our daughters pc, but when I installed it the pc wouldn't start; put her old memory back in and it was fine.

Then I tried the new memory in my pc, it only recognized 64 MB's and froze during startup. I put my memory back, now the computer boots up ok, but Windows won't start. I tried to start it using the last known configuration that worked, safemode and also from the installation disk; nothing works.

My two questions are: Why did this happen and how can I get XP to start?

The computers are a Gateway (hers) and a Dell (mine), both about seven years old, both take a maximum of 512 MB's of RAM and both Pentium 3's with Windows XP Home edition installed. The new memory is made by K-Byte and is (2) 256 MB 133MHZ SDR DIMM. Computer was off and unplugged at the time of installation; I have installed memory many times.

Thank you for any assistance.

 

Hello Hooch, welcome to Major Geeks.

I'm sorry to say that larger memory modules came after the chipsets and BIOS on your motherboards were designed.
These has memory chips that are organised in a way not recognisable (and therefore compatible) with you boards, as you have found out.

Your best bet is to got to Crucial and use their free calculator to get the specs for suitable memory upgrade even if you don't buy from them (recommended).

www.crucial.com
or
www.crucial.co.uk

If you would like to download Everest from MG (free) you can use it to find out about your motherboard memory controller and current modules.

http://www.majorgeeks.com/download4181.html

Post this info

Try resetting your bios on to get the Dell running.

Hope you can return the memory as unsuitable.

 

Thank you for the BIOS tip, I'll try it and post the results.

As far as the memory, the Dell already has (2) 256 MB modules installed and has worked fine, that's why I don't understand what happened. Also, one of the modules I've been using is made by K-Byte. Both computers are able to use (2) 256 MB modules for a total of 512 MB's.

Any other possibilities?

Thanks Again

 

Yes perhaps the modules are actually faulty.

But I don't think so since one was recognised as 64M. This is exactly what will happen with an older memory controller presented with a more modern module with larger chips than it can handle.

Exactly as I said.

The modern modules probably have fewer, larger capacity chips on them, not accessible to your controllers on the motherboard.

The total can still be 256M

Look at the modules and count the chips.

Post the results or photos.

Or do what I first said with Crucial or Everest.

 

You are exactly right!! The original memory has eight chips on both sides, while the new memory has eight chips on just one side; thank you for pointing that out to me, I love it when I learn something!

I got the Dell going again; clearing the BIOS didn't help, so I tried starting it with no memory, let it beep a few times, then turned it off and put the memory back...I was surprised when it started.

So, about that memory; would that mean I need that "double sided" memory I saw, or does it have some other name?

Thanks again studiot

 

Modern memory uses 256 megabit, 512megabit or 1gigabit chips. (note bit not byte)

To make 256 megabytes you require 8, 4 or 2 of these chips on a module.

Older memory uses 128 megabit or 64 megabit (or even less for older still) chips. To make a 256 megabyte module you would require 16 or 32 (not done) of these chips.

It is the job of the memory controller chip on the motherboard to recognise which chips are on the modules and issue the appropriate address signals to the module chips to the module to organise the bits into bytes.

The controllers on your motherboard cannot cope with splitting (figuratively speaking) the larger density chips to supply all 8 data line in the byte.

So yes it would appear you are limited to modules organised as 128x16, but not 256x8.
These last figures are how module (organisation) is specified.