What information exactly you need? Chipset manufacturer or what? Because there is no standard (eg. ASUS or Gigabyte) mainboard mounted inside laptop computer - it's made by Fujitsu Siemens for that specific model.
I had a friend looking at my notebook after it crashed. I kept keeping a stop 0x50 error message. He told me that it is probably the motherboard but he wasn't able to get FS spare parts. Any info available would be nice. I contacted FS support desk but since the warranty has expired they suggested to deassemble the notebook and check the different components. I deassmebled it as far as I could but wasn't able to see who made what.