11 years ago
  Buffalo (Memory)
  Mint (older version)
  Works perfectly
What works:

Both BIOS and OS (Mint 11 Katya, 12 Lisa) recognized it correctly.

What was done to make it work:

About Memory, [Lenovo ThinkPad X200s] is supported Up to 4GB essentially.

But, because I have updated BIOS to newest version (6DET68WW (3.18) ), BIOS could recognize 8GB RAM which I retrofitted correctly.

Additional notes:

PC3-8500 204Pin S.O.DIMM
8GB (4GBx2)

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