All disk manufacturers now have to ensure that any new model they bring to market uses 4K bytes per physical sector rather than the (old) standard of 512 bytes per physical sector. Drive manufacturers have tried to make these new AF drives backwards compatible, however there are still some compatibility issues with Windows. In fact, MS do not actually support 4K drives on Windows XP! Information on the backward compatibility of these drives can be found here. Information about the issues resolved by KB982018 can be read here. Dell also have some useful information about some potential issues here. For optimum performance, partitions on 4K AF drives should be alligned on a 4K byte boundary - it can make quite a difference to performance as you can see here. Most Windows 7 and Vista systems will already be correctly aligned, however XP systems and systems where partitions have been created using a third-party partition tool may not align the start of a partition to a 4K boundary. Dell have a Paragon Alignment tool which you may be of use only if you have a Dell system here. Note that some people have used a free version of the Paragon Alignment tool and lost all their data - so be warned! If you have Vista, there is an MS patch here. If you have Windows 7, you can check if a drive is the new type of 4K drive by first installing MS hotfix KB982018 and then running fsutil as follows:
If 'Bytes per Physical Sector' is not listed then you have not installed hotfix KB982018. Dell also have a utility DellAFDT.exe which you can download to check for AF drives and partition alignment.
Or you can use wmic in XP or later OS's to detect a 4K drive
In addition to Microsoft compatibility issues, some older storage drivers (e.g. early versions of the Intel iastor driver) do not support the new AF drives if your BIOS is in HDD AHCI mode - your image will BSOD if you try to place an old disk image onto one of these new 4K drives and boot it. To fix this on an Intel chipset platform, you would mean need to upgrade the Intel MSM driver (e.g. 8.9.4.1004) and replace it with a new IRST driver (e.g. 10.6.0.1002 or later). On Windows Vista/7 you may receive a pop-up error message “Windows setup could not
configure Windows to run on this computer’s hardware” if the driver needs updating. You can update the driver by disabling AHCI mode in the BIOS, booting the sysprep'ed old image and using CTRL-SHIFT-F3 at the first OOBE screen to reboot and enter Audit mode, then update the driver and then re-sysprep - generalize the image. Now you can take a copy of the hard disk and make a new image. Then change the BIOS back to AHCI HDD mode and see if it now boots OK. Known compatibility issuesThe following are known compatibility issues that may occur when you use large-sector drives:
Seagate USB GoFlex Hard Disk units - it seems the USB controller used in these external USB Hard Disk units only supports 4K Sector transfers and not 512e compatibility mode. As a result they may not work with many backup utilities or disk partition utilities - including RMPrepUSB! Contact the manufacturer and ask them to change the USB controller firmware! Check partition alignmentYou can use a simple vbs script to check the partition alignment of your hard disks. For best performance partitions should start on a 4K boundary. CheckAlign.vbs.
Type cscript Checkalign.vbs to run it (or double-click on the vbs file):
Trouble using some disk utilities with some AF drives?Most modern hard disks support 512e compatibility mode if they are AF drives, however some modern devices that contain Flash memory (such as USB FLash memory sticks, MP3 players, etc.) may not support 512e (and may not support XP or earlier operating systems). Disk utilities (such as RMPrepUSB) work with direct access to disk sectors. This means that a read of 1 sector from a 4K sector device will fail if the device does not support compatibility (512e) mode. However, a direct read of 8 sectors (8*512bytes=4K) will work. You can test this using RMPrepUSB Disk Doctore (hit Ctrl-D in RMPrepUSB) - if you set the No. Sectors value to 8 and the Start to 0 and then click on Sequential REad, it should complete successfully a read from a 4K non-compatible device, however a Sequential Read with the No. Sectors value of less than 8 will fail if the device does not support 512-byte compatibility mode. You will need to set a Start value using a modulo 8 value (e.g. 0,8,16,24,32, etc.) for the read to be successful. |
Advanced Format (4K sector) hard disks |