Hi,
both I and another users had this problem with the DX4000 not rebuilding automatically. In my case I (succesfully) solved the problem with the RST Intel driver which however has some pros and cons as it disable some DX4000 features (like display). In that case however I was also able to recover to the old installation by performing a recovery without loosing data.
Another user went through a more gentle method which however requires a little bit more of knowledge. I.e. he found on the DX4000 a folder with a slightly older driver of the in-built intel raid driver with respect to the one installed and working as default. After having shutdown the raid service he exchanged the file in the system directory with the slightly older one, rebooted and magically you find in the dashboard an Intel Raid Tab where you have a decent control of the RAID, including the possibility to migrate from Raid 1 to Raid 5 (Intel recover might be needed from control panel).
I tried myself this trick on both my two units and it worked flawlessly even if I already solved the problem with the standard Intel RST driver (in the meanwhile I think I went through 2 or 3 complete re-install for other reasons). I.e. I have in the dasboard a nice Intel tab folder which gives some more information about the RAID configuration
this is the link you can refer to:
regards
Davide
