8GB vs 12GB RAM in T440s

[igorkulman]

I have a T440s with 4GB RAM soldered to the board and 4GB in a slot. I found out I can replace the 4GB module in the slot with a 8GB module. My question is, will it break dual channel? Will the RAM be slower because of that? (but with greater capacity).

[Hans Gruber]

You would still get dual channel on 8GB of memory with 4GB is reserve. Dual channel in these modern machines is not as significant performance wise as it once was. A very fast SSD is probably the most important element to a T440s.