Question : Problem: Toshiba Satellite notebook fails to recognize over 448mb system memory

Facts:
Unit is Toshiba Satellite A-105 S1014 notebook.  WinXP Home.  Has worked flawlessly in all apps I care about since purchased.  However, installed RAM has ALWAYS read "448mb," both on MyComputer / Properties query window and on any system scan utility I run.  Always thought it was unusual, but never paid much attention.

Current RAM installed is original 512mb Kingston stick from unit purchase.  Wanted to add another 512mb.  Ran Crucial Technology's system scanner from Crucial website to determine correct upgrade stick.  Ordered/Received/Installed stick with no problem.  

However, no matter what configuration of RAM stick is in which socket, or whether ONE or BOTH sticks are installed, "installed memory" query will not read more than 448mb total  Both new stick and original stick work fine alone, in either socket.  Both give reads of  "448mb" when installed individually.  When BOTH are installed, system scan only shows ONE stick installed, and continues to read 448mb RAM installed.  I have been carefully to power off the unit and remove the battery before changing sticks.  I checked the BIOS settings to see if there is some sort of RAM "cap" at 448.  Didn't see anything.

How do I get a single RAM stick to register at least 500mb, and how can I get 2x512mb sticks to enable at least 1G system RAM?

3 Scans returned:

<1>  With new Crucial stick memory in M1

Memory Summary      
Location            System board or motherboard
Maximum Capacity      2048 MBytes
Memory Slots            2
Error Correction      None
Use                  System memory      
Device Set            M1
Device Locator           M1
Bank Locator            Channel B0
Capacity            512 MBytes
Memory Type            Synchronous DDR
Speed                  533 MHz
Data Width            64 bits
Form Factor            SODIMM
Total Width            64 bits

*************************************************************

<2>  With original Kingston memory stick in M2

Memory Summary      
Location            System board or motherboard
Maximum Capacity      2048 MBytes
Memory Slots            2
Error Correction      None
Use                  System memory      
Device Set            Channel B1
Device Locator                M2
Bank Locator            Channel B1
Capacity            512 MBytes
Memory Type            Synchronous DDR
Speed                  533 MHz
Data Width            64 bits
Form Factor            SODIMM
Total Width            64 bits

*************************************************************

<3> FINALLY - WITH ONE STICK IN M1 AND ONE IN M2

Memory Summary      
Location            System board or motherboard
Maximum Capacity      2048 MBytes
Memory Slots            2
Error Correction      None
Use                  System memory      
Device Set            M1
Device Locator           M1
Bank Locator            Channel B0
Capacity            512 MBytes
Memory Type            Synchronous DDR
Speed                  533 MHz
Data Width            64 bits
Form Factor            SODIMM
Total Width            64 bits

[SCAN DOESN'T DETECT  THE PRESENCE OF THE STICK INSERTED IN M2, OR THAT M2 IS PRESENT]

Answer : Problem: Toshiba Satellite notebook fails to recognize over 448mb system memory

Well, first let's clear up the 448MB indication ==> the problem you're having now is that the system is only recognizing 512MB (i.e. one module) instead of the installed 1024MB.   It has always correctly recognized the installed 512MB ... it has simply had another use for some of that memory :-)  ...

The "missing" 64MB is the memory being used by your video adapter.   So even if the system recognized both modules, you'd only "see" 960MB  (or possibly less -- sometimes the BIOS will allocate more memory for video if more is installed ... although with 64MB already allocated I don't think that's the case here).

As for why it's not seeing the 2nd module ==> this MAY be a memory bank/density issue.   Is the original module single or double sided?   What about the Crucial module?

... it shouldn't hurt to update the BIOS => but none of the release notes for recent modifications indicate any fixes to the memory recognition code.   Doesn't mean something wasn't changed ... but I'd say it's unlikely it will help here.
Here's the current BIOS page for your laptop:  http://www.csd.toshiba.com/cgi-bin/tais/su/su_sc_dtlViewDL.jsp?soid=1707190&moid=1209133&rpn=PSAA2U&sn_mpn=null&BV_SessionID=@@@@1665432331.1193105434@@@@&BV_EngineID=cccgaddmflilldecgfkceghdgngdgmm.0&ct=DL&all_docs=false

If the memory modules are different densities, there's a good chance that's your issue.   You might also double-check in the BIOS to see if there are any settings for the shared video memory that might need to be updated with larger amounts of memory [this would be VERY unusual -- but I long ago learned that anything's possible :-) ]