The problem I've been experiencing is very similar to this old one from server 2000:
http://support.microsoft.com/kb/290757
After a system restart, the write-caching policy is not being saved on the server and the settings are not persistent.
The system hardware is an Intel RST express chipset, and the Intel Raid 5 Volume (Microsoft version) driver is 6.2.9200.16384 (win3_rtm.120725-1247)
are there any hotfixes available for this driver to correct the problem on server 2012?