Both BIOS and OS (Mint 11 Katya, 12 Lisa) recognized it correctly.
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.
PC3-8500 204Pin S.O.DIMM
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