Thinkpads Forum

I have a T400 and it came with 2 x 1gb memory modules
I have bought one 4gb memory module
I opened the case and removed the 2 old memory modules and put the new 4gb module into the first slot that is below, and then replaced one of the old 1gb modules in the slot above and put the case back on.
All is working fine but my question is
Is there a preferred order I should have done? I mean did I put them in the right slots or does it not matter which order you do it in?

I can't answer that since I use the same cards in both slots in all of my systems, but do you have a 32 bit or 64 bit OS loaded?

Welcome to the forum.
Either way is fine, usually the bottom slot (0) is filled first with the largest module.

Hi thanks for the repies, I am using 64bit linux system
I just wondered if there was a preferred order, anyway I did put the 4gb in the first (bottom) slot and the older 1gb on the top and all is working fine.

In this chipset Slot 0, the bottom slot, needs to have memory in it or the computer will not boot.

In practice it's more practical to put the bigger stick in the lower slot so if you upgrade the smaller ram in the future you don't need to remove things unnecessary. I don't think it matters otherwise.

The slot under the keyboard get filled first. Always largest of first whichever comes first. This is how stock configuration comes when new.
On older series before T400/500, bottom slot first under the palmrest.

Cheers, thinkpadcollection