Disk Geometry Puzzler

How to use TestDisk to recover lost partition
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Posts: 2
Joined: 27 Mar 2013, 06:59

Disk Geometry Puzzler

#1 Post by treyrhodes »

I am attempting to use TestDisk on an external HDD formerly used in a MacBook Pro. The drive seems to be in good mechanical order. My question is about the geometry. Knowing the correct values is of course, essential to recovery of my deleted partition.

Here is the weird part. The disk itself is a Toshiba MK1059GSM and it has the following values printed on its label:
8455MB (CYL16383 H16, S63)
1TB (LBA 1,953,525, 168 Sectors)

I take this to mean that is has physical C/H/S values of 16383/16/63. Is this valid assumption?

The Toshiba website, however, claims the following about this part: http://storage.toshiba.eu/cms/en/hdd/mu ... ductid=364
    Number of platters 3
    Number of cylinders 187,199
    Number of heads 6
    Bytes/sector (Host) 512
    Bytes/sector (Disk) 4096 kByte
Now, when I use TestDisk it seems to want to use different C/H/S values by default and warns me that H should be 8 and not the default 16. I am totally perplexed. What values might I use? Any help would be greatly appreciated!

Posts: 2
Joined: 27 Mar 2013, 06:59

Re: Disk Geometry Puzzler

#2 Post by treyrhodes »

No one? Hrm...