Hello! I can't tell you how happy I have been, after being able to convert a 2nd hand generic 4Mb RAM that I bought for 20 US dollars (everything is expensive in Japan but it's considered to be very cheap in this respect...) for my laptop. I don't know what make it is since I bought it from a tatty second hand shop! I only know it operates at 80ns and is produced by Toshiba. I'll try to get some useful info to you tomorrow. Memory banks are on both sides of the chip. Bank 4 (see diagram) is very close to the 0 ohm resistors which are placed directly about pins 69-70. One can see the tracks directly linking pins.

A diagram of the module:

Before conversion:


+------------------------------------------------------------------------+
|                                                                        |
|                                                                        |
|        bank1            bank 2           bank 3          bank4         |
|                                                                        |
+-+                                                           xxox       |
  |1 |||||||||||||||||||||||||||||  __  ||||||||||||||||||||||||||||  72 |
  +--------------------------------+  +----------------------------------+
                                    Round notch about 2mm deep

o= open connection
x= zero ohm resistor


After conversion:


+------------------------------------------------------------------------+
|                                                                        |
|                                                                        |
|        bank1            bank 2           bank 3          bank4         |
|                                                                        |
+-+                                                           ooxx       |
  |1 |||||||||||||||||||||||||||||  __  ||||||||||||||||||||||||||||  72 |
  +--------------------------------+  +----------------------------------+
                                    Round notch about 2mm deep

Now......my next project is to find a cheap hard disk suitable for my little machine. Can you give me some idea....there are 2.5 mm IBM hard disks available for PS/2 55. I wonder how to convert them, if possible.

Best regards from Japan

William