How to upgrade thinkpad t42 memory from 512MB to 2GB

[B_Hodge]

I have a T42 and I would like to upgrade to 2GB but am a bit confused. I want to upgrade its memory. It currently has one 512 MB PC2700 (DDR333) memory module. If I add another memory module to the empty bank, can it be PC2100 (DDR266) or PC3200 (DDR400) or does it have to be PC2700?

[Arley]

I think it is not possible to upgrade memory upto 2 GB. Memory Upgrade for IBM ThinkPad T42 2378-xxx Laptop, the IBM ThinkPad T42 2378-xxx Laptop takes the PC2100/2700 DDR SDRAM SODIMMs Memory Type, and comes installed with of Memory. Choose from the following IBM ThinkPad T42 compatible memory modules listed below. Adding memory to your ThinkPad T42 is the quickest and easiest upgrade you can make that will result in faster system performance.

[Alchmey]

The T42 does not support dual channel memory so there is no benefit to be gained by using the same size memory modules. The important thing is to get more memory. You can upgrade your IBM ThinkPad T42 2378-xxx Laptop to up to a maximum of 2.0 GB Memory, the system has 2 sockets to install Memory, already with standard Memory installed. You can use DDR 400 Mhz SO DIMM ram with your current ram stick. i would get another 512 mb stick to enable dual channeling.

[Aditya kumar]

Determine the proper size and speed of the memory you want to add. This can be found in the BIOS, For best Laptop performance use the maximum amount of allowed Memory per slot for your Laptop. Choose the following Memory Upgrade for IBM ThinkPad T42 2378-xxx Laptop.
512MB Module->512MB-DDR333, 333MHz, PC2700, 200p SODIMM, 2.5v, Sync
1GB Module->1024MB-DDR266, 266MHz, PC2100, 200p SODIMM, 2.5v, Sync