OK,
Did a bit more digging and perhaps there is a feature of this drive that is causing the mayhem.
Taken from:
http://forums.seagate.com/t5/Barracuda-XT-Barracuda-and/FreeAgent-GoFlex-DESK-2TB-Unknown-HDD-ST2000DL001/m-p/74231Re: FreeAgent GoFlex DESK 2TB --- Brand New HDD [ST2000DL001]
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SeaTools makes no mention of the drive's 4KB physical sectoring, so I'm wondering whether it is Advanced Format aware. HD Sentinel reports that the drive has long physical sectors, each being equivalent to 8 logical sectors. This suggests that software will still need to communicate with the drive on a 512-byte basis, but the drive will handle data transfers internally as 4096 byte sectors.
AISI, the relationship between physical 4KB sectors and 512-byte LBAs is as follows:
Physical Sector 0 = LBA 0 - 7
Physical Sector 1 = LBA 8 - 15
Physical Sector 2 = LBA 16 - 23
...
Physical Sector 7 = LBA 56 - 63
Physical Sector 8 = LBA 64 - 71
Microsoft Vista and Windows 7 will create 4KB aligned partitions by default. However Windows XP will divide the drive into logical tracks, each consisting of 63 logical sectors. This means that each 4KB NTFS cluster will span two physical sectors, requiring two revolutions of the platters each time an LBA needs to be written. This is because the whole 4KB physical sector is first read, then 512 bytes are modified, new ECC bytes are computed, then the entire 4KB physical sector is written back to the drive. OTOH, if each 4KB cluster is aligned to a corresponding physical sector, then the sector can be written on the fly.
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FWIW, I noticed the following marketing-speak in the datasheet:
"Seagate SmartAlign technology delivers a new level of simplicity for Advanced Format 4K drives. While other Advanced Format drives require the use of additional software utilities during integration, the Barracuda Green drive with Seagate SmartAlign technology requires no extra time or steps."
I have no idea how SmartAlign works.
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So, is boot1h being auto-aligned away from where boot0 expects it to be ?