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My laptop fails to boot up. Since it fails even before I could enter bios settings, I thought it has to be a hardware failure. To rescue my data, I removed the hard disk and plugged it to another PC. There I noticed that the partition table is incorrect, but I was able to rescue my data using the testdisk tool. Is it possible, that it is indeed a software error (meaning I could repair my laptop by repairing the partition table), although it even fails to enter bios?

The laptop is a Samsung Series7 700Z3C. It doesn't boot up, whether there is a bootable CD in the drive or not and whether the internal hard drive is removed or plugged in. When pressing the power button, it just shows a black screen and nothing else. I can hear the cd drive running, but the CPU fan isn't moving.

It fails before I could enter bios, so I couldn't change boot priority which is set to hard drive first (I think). I tried to repair the partition table of the hard disk(see below), but the laptop has a second hard drive (a small SSD) which is soldered, so I can't do anything here.

Repairing partition table

The testdisk utility could recognize the correct partition table, but when I tried to write it to the hard disk, I got a "Partition: Write error". Here the testdisk.log (I didn't log it the first time I ran it, so this probably isn't the log of the correct repair process, but the log of testdisk running later on the already repaired disk)

Fri Jan  4 16:17:33 2013
Command line: TestDisk

TestDisk 6.13, Data Recovery Utility, November 2011
Christophe GRENIER <grenier@cgsecurity.org>
http://www.cgsecurity.org
OS: Linux, kernel 3.5.0-21-generic (#32-Ubuntu SMP Tue Dec 11 18:51:59 UTC 2012) x86_64
Compiler: GCC 4.7
Compilation date: 2012-10-01T13:00:04
ext2fs lib: 1.42.5, ntfs lib: libntfs-3g, reiserfs lib: none, ewf lib: none
/dev/sda: LBA, HPA, LBA48, DCO support
/dev/sda: size       625142448 sectors
/dev/sda: user_max   625142448 sectors
/dev/sda: native_max 625142448 sectors
/dev/sda: dco        625142448 sectors
Warning: can't get size for Disk /dev/mapper/control - 0 B - CHS 1 1 1, sector size=512
Hard disk list
Disk /dev/sda - 320 GB / 298 GiB - CHS 38913 255 63, sector size=512 - TOSHIBA MK3233GSG,     S/N:8027W1BQW, FW:QS002A
Disk /dev/sdb - 750 GB / 698 GiB - CHS 11400 255 63, sector size=4096 - Hitachi     HTS727575A9E364
Disk /dev/mapper/crypt - 287 GB / 267 GiB - CHS 561721336 1 1, sector size=512
Disk /dev/mapper/system-HOME - 263 GB / 245 GiB - CHS 514850816 1 1, sector size=512
Disk /dev/mapper/system-ROOT - 19 GB / 18 GiB - CHS 39059456 1 1, sector size=512
Disk /dev/mapper/system-SWAP - 3997 MB / 3812 MiB - CHS 7806976 1 1, sector size=512
Disk /dev/dm-0 - 287 GB / 267 GiB - CHS 561721336 1 1, sector size=512
Disk /dev/dm-1 - 19 GB / 18 GiB - CHS 39059456 1 1, sector size=512
Disk /dev/dm-2 - 3997 MB / 3812 MiB - CHS 7806976 1 1, sector size=512
Disk /dev/dm-4 - 263 GB / 245 GiB - CHS 514850816 1 1, sector size=512

Partition table type (auto): Intel
Disk /dev/sdb - 750 GB / 698 GiB - Hitachi HTS727575A9E364
Partition table type: Intel

Analyse Disk /dev/sdb - 750 GB / 698 GiB - CHS 11400 255 63
Geometry from i386 MBR: head=255 sector=63
check_part_i386 failed for partition type 07
check_part_i386 failed for partition type 07
check_part_i386 failed for partition type 07
get_geometry_from_list_part_aux head=255 nbr=1
get_geometry_from_list_part_aux head=255 nbr=1
Current partition structure:
Invalid NTFS or EXFAT boot
 1 P HPFS - NTFS              0  32 33    12 223 19     204800
 1 P HPFS - NTFS              0  32 33    12 223 19     204800
Invalid NTFS or EXFAT boot
 2 P HPFS - NTFS             12 223 20  8802 254 53  141213337
 2 P HPFS - NTFS             12 223 20  8802 254 53  141213337
 3 E extended LBA          8803   0  1 87913  48  7 1270905181
Invalid NTFS or EXFAT boot
 4 P HPFS - NTFS          87913  48  8 91201  52 51   52822016
 4 P HPFS - NTFS          87913  48  8 91201  52 51   52822016
No partition is bootable

test_logical: 
Partition sector doesn't have the endmark 0xAA55
Computes LBA from CHS for Disk /dev/sdb - 750 GB / 698 GiB - CHS 11401 255 63
Allow partial last cylinder : Yes
search_vista_part: 1

search_part()
Disk /dev/sdb - 750 GB / 698 GiB - CHS 11401 255 63
NTFS at 0/4/5
filesystem size           25600
sectors_per_cluster       1
mft_lcn                   8533
mftmirr_lcn               2
clusters_per_mft_record   -10
clusters_per_index_record 1
     HPFS - NTFS              0   4  5     1 155 26      25600 [SYSTEM]
     NTFS, 104 MB / 100 MiB
NTFS at 1/155/27
Warning: Incorrect number of bytes per sector 512 (NTFS) != 4096 (HD)
filesystem size           141213337
sectors_per_cluster       8
mft_lcn                   786432
mftmirr_lcn               2
clusters_per_mft_record   -10
clusters_per_index_record 1
     HPFS - NTFS              1 155 27  1100  95 39   17651667
     NTFS, 72 GB / 67 GiB

recover_EXT2: s_block_group_nr=0/111, s_mnt_count=72/4294967295, s_blocks_per_group=32768,     s_inodes_per_group=8176
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 3662080
recover_EXT2: part_size 3662080
     Linux                 1100  96 21  1328  84 36    3662080
     EXT4 Large file Sparse superblock, 14 GB / 13 GiB
     Linux Swap            1328  88 41  1510 177  9    2929406
     SWAP2 version 1, 11 GB / 11 GiB

recover_EXT2: s_block_group_nr=0/4646, s_mnt_count=71/4294967295, s_blocks_per_group=32768, s_inodes_per_group=8192
recover_EXT2: s_blocksize=4096
recover_EXT2: s_blocks_count 152271104
recover_EXT2: part_size 152271104
     Linux                 1510 181 16 10989  37 56  152271104
     EXT4 Large file Sparse superblock, 623 GB / 580 GiB
NTFS at 10989/37/57
Warning: Incorrect number of bytes per sector 512 (NTFS) != 4096 (HD)
filesystem size           52822016
sectors_per_cluster       8
mft_lcn                   786432
mftmirr_lcn               2
clusters_per_mft_record   -10
clusters_per_index_record 1
     HPFS - NTFS          10989  37 57 11400  38 30    6602752 [SAMSUNG_REC]
     NTFS, 27 GB / 25 GiB

Results
     HPFS - NTFS              0   4  5     1 155 26      25600 [SYSTEM]
     NTFS, 104 MB / 100 MiB
     HPFS - NTFS              1 155 27  1100  95 39   17651668
     NTFS, 72 GB / 67 GiB
     Linux                 1100  96 21  1328  84 36    3662080
     EXT4 Large file Sparse superblock, 14 GB / 13 GiB
     Linux Swap            1328  88 41  1510 177  9    2929406
     SWAP2 version 1, 11 GB / 11 GiB
     Linux                 1510 181 16 10989  37 56  152271104
     EXT4 Large file Sparse superblock, 623 GB / 580 GiB
     HPFS - NTFS          10989  37 57 11400  38 30    6602752 [SAMSUNG_REC]
     NTFS, 27 GB / 25 GiB

interface_write()
 1 P HPFS - NTFS              0   4  5     1 155 26      25600 [SYSTEM]
 2 P HPFS - NTFS              1 155 27  1100  95 39   17651668
 3 E extended LBA          1100  96  1 10989  37 57  158863124
 4 P HPFS - NTFS          10989  37 57 11400  38 30    6602752 [SAMSUNG_REC]
 5 L Linux                 1100  96 21  1328  84 36    3662080
 6 L Linux Swap            1328  88 41  1510 177  9    2929406
 7 L Linux                 1510 181 16 10989  37 56  152271104
write!

write_mbr_i386: starting...
write_all_log_i386: starting...
write_all_log_i386: CHS: 1100/96/1,lba=17677548
write_all_log_i386: CHS: 1328/87/1,lba=21339801
write_all_log_i386: CHS: 1510/180/1,lba=24269490

Partition: Write error

TestDisk exited normally.

But although it always reports this error, I noticed after a few runs, that the partition table now seems to be correct. But the laptop still doesn't boot up.

I ran fdisk and noticed that it reports a wrong logical sector size. I can check that, because I have a second laptop that has exactly the same hardware, which should also have exactly the same partition table. This second laptop is still working perfectly well. Here the fdisk output of the harddisk of the first (broken) laptop:

Hinweis: Die Sektorgröße ist 4096 (nicht 512)

Befehl (m für Hilfe): p

Disk /dev/sdb: 750.2 GB, 750156374016 bytes
255 Köpfe, 63 Sektoren/Spur, 11400 Zylinder, zusammen 183143646 Sektoren
Einheiten = Sektoren von 1 × 4096 = 4096 Bytes
Sector size (logical/physical): 4096 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Festplattenidentifikation: 0xfabded4a

   Gerät  boot.     Anfang        Ende     Blöcke   Id  System
/dev/sdb1             256       25855      102400    7  HPFS/NTFS/exFAT
/dev/sdb2           25856    17677523    70606672    7  HPFS/NTFS/exFAT
/dev/sdb3        17677548   176540671   635452496    f  W95 Erw. (LBA)
/dev/sdb4       176540672   183143423    26411008    7  HPFS/NTFS/exFAT
/dev/sdb5        17677568    21339647    14648320   83  Linux
/dev/sdb6        21339904    24269309    11717624   82  Linux Swap / Solaris
/dev/sdb7        24269568   176540671   609084416   83  Linux

If you're not familiar with german, the first line says "Notice: Sector size is 4096 (not 512)". Another noteable thing is, the line

Sector size (logical/physical): 4096 bytes / 4096 bytes

Here the fdisk output of the correctly working laptop:

The device presents a logical sector size that is smaller than
the physical sector size. Aligning to a physical sector (or optimal
I/O) size boundary is recommended, or performance may be impacted.

Befehl (m für Hilfe): p

Disk /dev/sda: 750.2 GB, 750156374016 bytes
255 Köpfe, 63 Sektoren/Spur, 91201 Zylinder, zusammen 1465149168 Sektoren
Einheiten = Sektoren von 1 × 512 = 512 Bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Festplattenidentifikation: 0xfabded4a

   Gerät  boot.     Anfang        Ende     Blöcke   Id  System
/dev/sda1   *        2048      206847      102400    7  HPFS/NTFS/exFAT
/dev/sda2          206848   707418111   353605632    7  HPFS/NTFS/exFAT
/dev/sda3      1412325376  1465147391    26411008   27  Hidden NTFS WinRE
/dev/sda4       707420158  1412323327   352451585    5  Erweiterte
Partition 4 does not start on physical sector boundary.
/dev/sda5       736716800   760152063    11717632   82  Linux Swap / Solaris
/dev/sda6       760154112  1412323327   326084608   83  Linux
/dev/sda7       707420160   736716799    14648320   83  Linux

Partitionstabelleneinträge sind nicht in Platten-Reihenfolge

The last line says "Partition table entries are not in the order of the hard drive". As you can see, the logical sector size here is different. Is this important?

What could be the reasons the laptop doesn't boot up? What would be the next steps to solve the problem?

edit:

First occurrence of the problem

The laptop has installed the original Windows and an additional Ubuntu. I tried to upgrade Ubuntu 12.04 to 12.10.

After upgrading it, grub reported an error. So I booted it up from a live cd, entered the ubuntu system via chroot and then reinstalled grub. I installed it to both the installed hard drives - /dev/sda (the hdd) and /dev/sdb (the SSD).

After that, I rebooted the laptop without the live cd and it started up. Everything seemed to work well, but then I tried to reboot it again and the error was there. From then on up to now I wasn't even able to enter the bios settings.

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2  
Standard diagnostics say to remove EVERYTHING that is connected to the motherboard (Ram, drives, modem if present, wireless, keyboard, touchpad, etc.) then add a KNOWN GOOD stick of Ram, connect a working display, and power the unit on. If the laptop isn't going to require some serious attention, it should show a BIOS splash screen. –  Bon Gart Jan 4 '13 at 15:55
1  
It even should 'work' without RAM. (Where work is defined as in the 'Halp halp! No RAM found error - usually three beeps'. -- And to make some of @arashams comment more explicit: Did you try an external screen? –  Hennes Jan 4 '13 at 16:00
2  
Bottom line...if it won't POST, it's doesn't matter what condition your hard drive is in. Or any other boot media for that matter. Try the external monitor. If that results in the same issue, the system board is likely gone bad. –  CharlieRB Jan 4 '13 at 16:02
1  
@user184557 - Sound taps ;) Sounds like the motherboard is dead. –  Everett Jan 4 '13 at 16:16
1  
Ok. So, the issue is that you don't understand why you need to remove everything... even though you think you do understand why, and you believe the reasons are ignorable. A Bad Keyboard can cause a laptop not to POST. A short in a broken Touchpad cable can cause a laptop not to POST. A Bad optical drive can cause a laptop not to POST. A fried wireless card can cause a laptop not to POST. Can you see a pattern here? Until you have eliminated/removed all the possibilities, you can't know any probabilities. For all you know, your issue could be a bad optical drive. –  Bon Gart Jan 4 '13 at 16:45

2 Answers 2

Have you tried resetting the BIOS ? If altering partition table of hard drives didn't work then the problem may not be with hard drives. BIOS contains initial instructions for the system, so this might indicate that the laptop failed to initialize in the first place. here is a link. You can skip to step 3 because getting into BIOS is not available.

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Link only answers (which this effectively is) aren't good answers. Please summarise the relevant part of the page you link to. –  ChrisF Feb 15 '13 at 17:47
    
ow sorry kinda new here. so the steps are quite the same as removing cmos battery of a desktop pc, even easier for laptops. on the back side of the laptop there should be a few compartments. i can't pinpoint exactly which one holds the cmos batt, u can unscrew and findout yourself. then, take out the cmos batt, wait for a few minutes to let the laptop discharges itself of remaining electricity n then replace with a new battery. –  user199574 Feb 15 '13 at 19:56

Is it a fairly newer laptop? Do you maybe get a blank screen with a blinking curser? I hope this isn't your problem, but in some newer laptops the GPU screws up.... and will do everything from tell you the harddrive isn't connected right, to not booting at all... on acers you test by pressing below the windows key while you boot to put pressure on the gpu and if it's the GPU it will boot.... the problem is caused by the switch to lead free solder... it looks different when it's gotten hot enough so they aren't getting it hot enough, which leads to a bad connection... as the solder heats and cools over time the connection is damaged... If you google you might be able to find the location of the gpu in that model and put pressure (lots of it) over the gpu while you attempt to boot the computer, or just open it up and put pressure on the gpu while booting if you aren't afraid of getting electrocuted.

I found that problem when I was working on a laptop I bought from craigslist that supposedly just had a failed harddrive, but it wouldn't even boot from cd to install windows on a drive I had. I closed it and set my hot gateway laptop on top of it to look up some stuff. When I was finished I tried booting the bad one and it booted (probably the heat and weight of the other laptop)... unfortunately it only booted from cd and couldn't install windows... then stopped working again... still haven't gotten around to taking a heat gun to the gpu (and got a second laptop with the same problem!)

The other possibility is that the cpu or memory got bumped... remove the memory and put it back in... if that doesn't fix it do the same with the cpu... laptops - like desktops - usually have 3 reasons to not at least boot to bios: Video, CPU, Memory (otherwise it's probably the motherboard)

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