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I had a nice software raid 1 (using windows 7 raid) working when one of my drives failed. I replaced it by another one (WD blue 1 TB) which uses 4k sectors, and this makes windows unhappy (Cannot create mirrored drive with different sectors sizes)

I totally understand but, because my 4k sectors hard drive uses Advanced Format, it should be able report 512 sectors.

DiskCheckup utility indeed reports 4k for physical sector size and 512 for the logical sector size.

Is there a way to make those disks work nicely with the win 7 software raid ?

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Possible, but the OP didn't mention if his disk supports 512 byte logical sectors (mine does) – Dinaiz Jan 7 '13 at 15:05

Did you install this update? Perhaps it might help. If not, it appears that Windows' built-in software RAID operates at a lower level than the emulated sectors.

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Yeah I did but no luck ... – Dinaiz Jan 7 '13 at 15:01
Doesn't look doable then. There must be some serious performance issues with using mismatched physical sector sizes, which is why it's unsupported. – Bigbio2002 Jan 7 '13 at 15:31

Advanced Format means sector size larger than 512-bytes, 4 KB in your case.

One needs "Advanced Format 512e" to be able to simulate 512-byte sectors, which the WD Advanced Format paper says it does support.

Perhaps the problem is that your disk was formatted with the default sector size, which is probably 4K. You might try to reformat it with 512-byte sectors.

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Yep that's my uderstanding too. Is it possible to change the sector size when formating a drive ?! Or did you mean align ? – Dinaiz Jan 7 '13 at 23:47
I meant the normal Windows format from Computer Management / Disk Management. Right-click the disk and choose Format, then in "Allocation unit size" choose 512. – harrymc Jan 8 '13 at 7:59
Aren't you mixing cluster size and sector size ? – Dinaiz Jan 8 '13 at 23:40
"Unit size" is the only size you can specify in Windows, so is the only advice I can think of toward solving your problem. Try it and see if it helps. Otherwise your only hope would be WD calibration software (which I have no experience with). – harrymc Jan 9 '13 at 7:37
Thanks, I tried to change the allocation unit size but no luck. Now trying WD calibration thing ... – Dinaiz Jan 9 '13 at 15:19

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