I have a hard time letting go of my old systems. I don't hook it up to the internet anymore but I keep my old windows 2000 system running since it's all set up the way I like it and it runs sweetly in 1GB.
Anyway, I digress, I would try some USB WD 4TB drives on this system and some would work and others wouldn't work at all.
I finally found the answer.
It has to do with old style DOS partition tables and 512 byte sector sizes.
See, an old style DOS partition table would hold a 32 bit value for the number of sectors, that being 2^32 or 4G sectors.
Now the old hard drives had 512 byte sectors so the max partition size would be 2^32 * 512 bytes = 2.1 TB or 2TB.
If we had a 4096 byte sector, the max partition size would be 2^32 * 4096 bytes = 17592186044416 or 16TB.
I had one drive that didn't work under windows 2000 and plugging it into a linux box, "fdisk -l" told me that it had 512 logical but 4096 physical. So it's actually 4096 byte sectors but it's pretending to be a 512 byte sector for compatibility.
So how to get it to do the 4096 byte sectors? Use the WD Quick Formatter utility:
How to format external drives using WD Quick Formatter in Windows ...
https://support.wdc.com/knowledgebase/answer.aspx?ID=3868
If you format the drive in "XP Compatible" mode it will put the drive into a 4096 byte sector size.
After running the utility and plugging it into a linux box, fdisk tells me that this is a 4096/4096 drive.
Doing this to a 10TB drive WD from bestbuy's black friday sale...
Disk /dev/sdc: 9.1 TiB, 10000831348736 bytes, 2441609216 sectors
Units: sectors of 1 * 4096 = 4096 bytes
Sector size (logical/physical): 4096 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: dos
Disk identifier: 0xd841c1a1
Device Boot Start End Sectors Size Id Type
/dev/sdc1 256 2441609215 2441608960 9.1T 7 HPFS/NTFS/exFAT
One mystery solved that has bothered me for a while.
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