Mfrs | ,---- Samsung ----. ,--------- Other ---------. U u DIMMs | 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 C | 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 o | 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 0 d | 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 8 9 9 0 0 8 e | 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 | 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 R | 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 e | 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 v | 0 0 1 1 1 1 1 1 1 1 0 0 0 0 0 0 1 1 2 2 0 0 0 0 0 s Systems | 4 5 0 1 2 3 4 5 8 9 2 3 6 7 8 9 6 7 0 1 1 2 1 2 1 -------------+-------------------------------------------------- / 0002000001 | o o o o o o o o o o o o o o o o o o o o o o o o 6 0002000008 | o o o o o o o o o o o o o o o o o o o o o o o o \ 0002000009 | x x x x x x x x x x o o o o o o o o o o o o o o / 0002000003 | o o o o o o o o o o o o | 0002000004 | o o | 0002000005 | x x x x x x x x x x o o o o o o o o o o o x o o A 0002000006 | o o o o | 0002000007 | o o | 0002000010 | o o o o | 0002000011 | o o o o \ 0002000012 | o o o o U 0002000002 | o o = working x = not working U = unknown CPU microcode revision or DIMM manufacturer (units not available at time of testing) Systems and DIMMs are identified by Libiquity serial numbers. Error Details ============= Unit 0002000009 with Samsung DIMMs ---------------------------------- Screen and backlight never turn on. Bluetooth LED never turns on. Halts immediately on power button press. die() or other failue in raminit in romstage? Unit 0002000005 with Samsung DIMMs ---------------------------------- Screen and backlight never turn on. Bluetooth LED does turn on. Power button must be held for several seconds to halt. Hang somewhere in ramstage? Unit 0002000005 with DIMM 0009000002 (Elpida, 2 GiB, 2Rx8) ---------------------------------------------------------- First attempt: Boots to payload. GRUB prints the following: Welcome to GRUB! symbol `grub_relocator_new' not found Aborted. Press any key to exit. Second attempt: Boots to payload. GRUB shows menu. Third attempt: Screen and backlight turn on. Bluetooth LED turns on. Screen remains black (no output from GRUB). Halts immediately on power button press. Fourth attempt: Boots to payload. GRUB prints the following: Welcome to GRUB! error: variable `prefix' isn't set. error: variable `prefix' isn't set. error: variable `prefix' isn't set. symbol `grub_gfxmenu_try_hook' not found Aborted. Press any key to exit. Fifth attempt: Boots to payload. GRUB prints the following: Welcome to GRUB! symbol `grub_relocator_new' not found Aborted. Press any key to exit. Sixth attempt: Screen and backlight turn on. Bluetooth LED turns on. Screen remains black (no output from GRUB). Halts immediately on power button press. Seventh attempt: Boots to payload. GRUB prints the following: Welcome to GRUB! symbol `grub_relocator_new' not found Aborted. Press any key to exit. Eighth attempt: Boots to payload. GRUB prints the following: Welcome to GRUB! symbol `grub_relocator_new' not found Aborted. Press any key to exit. Ninth attempt: Boots to payload. GRUB shows menu. Tenth attempt: Boots to payload. GRUB shows menu. Eleventh attempt: Boots to payload. GRUB shows menu. Twelfth attempt: Screen and backlight turn on. Bluetooth LED turns on. Screen remains black (no output from GRUB). Halts immediately on power button press. Conclusions =========== Some X200 units running libreboot don't work with any Samsung DIMMs. The CPU microcode revision does not seem to affect DIMM compatibility as previously suspected, since two of the three tested units with revision 0x6 work with Samsung DIMMs and one of the eight tested units with revision oxA doesn't work with Samsung DIMMs. Some other factor must exist that is the same between units 0002000009 and 0002000005 and between the other nine tested units but different between the former and latter groups of tested units. A possible difference in GMCH steppings was considered. However, lspci (`lspci -s 00:00.0 -nn -vvv`) reported "rev 07" for bus 0x00, device 0x00, function 0x0 on units 0002000001, 0002000008, and 0002000009.