$ sudo hexedit /dev/pmem0 Cut and paste 5361792048656c6c6f20746f204d79204c6974746c6520467269656e64 into hexedit: 00000000 53 61 79 20 48 65 6C 6C 6F 20 74 6F 20 4D 79 20 Say Hello to My 00000010 4C 69 74 74 6C 65 20 46 72 69 65 6E 64 00 00 00 Little Friend... 00000020 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000030 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000040 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000050 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000070 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000080 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000090 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000E0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000000F0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000100 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000110 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000120 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000130 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000140 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000150 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000160 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ --- pmem0 --0x0/0x100000000--------------------------------------------- Ctrl-X and Y to save. $ sudo hexedit /dev/pmem0 will display what we pasted. Ctrl-X to exit. At this point, you can do a graceful Restart, pull the power cables from the back of the computer, whatever type of power cycle test you want. Once the computer is back on and you login and get back to a terminal, check the contents of /dev/pmem0 again. In my case, it is zeros at 0x000 but has stuff at 0x400. I expected it to be what I pasted in above. 00000400 00 00 04 00 00 00 10 00 CC CC 00 00 69 B3 0F 00 ............i... 00000410 F4 FF 03 00 00 00 00 00 02 00 00 00 02 00 00 00 ................ 00000420 00 80 00 00 00 80 00 00 00 20 00 00 00 00 00 00 ......... ...... 00000430 65 7A B5 54 01 00 18 00 53 EF 00 00 01 00 00 00 ez.T....S....... 00000440 64 7A B5 54 00 4E ED 00 00 00 00 00 01 00 00 00 dz.T.N.......... 00000450 00 00 00 00 0B 00 00 00 00 01 00 00 38 00 00 00 ............8... 00000460 02 00 00 00 03 00 00 00 D6 C5 30 FC 9E 54 42 27 ..........0..TB' 00000470 B5 4D 44 4F 15 A5 5C CB 00 00 00 00 00 00 00 00 .MDO..\......... 00000480 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000490 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000004A0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000004B0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000004C0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 FF 00 ................ 000004D0 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 000004E0 00 00 00 00 00 00 00 00 00 00 00 00 43 63 EE 31 ............Cc.1 000004F0 CA F3 4D DD AF DB 00 5E A9 D3 70 6D 01 00 00 00 ..M....^..pm.... 00000500 00 00 00 00 00 00 00 00 64 7A B5 54 00 00 00 00 ........dz.T.... 00000510 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000520 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000530 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000540 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00000550 00 00 00 00 00 00 00 00 00 00 00 00 1C 00 1C 00 ................ --- pmem0 --0x400/0x100000000------------------------------------------- This occurs with both Ross's prd and Boaz's pmem trees both at HEAD.