(I am posting here because i came across information via google that indicated the root cause to this problem was a windows update).
I have ASUS P5N-E SLI which has nVidia nForce 650i SLI, with Vista Ultimate 64 - all latest service packs installed. I purchased this system pre configured from a 3rd party vendor.
Recently, the system spewed forth "Missing BOOT MGR" message while attempting to power up the system. A bit of research lead me to attempt to boot from my Vista Ultimat 64 SP1 DVD. In the middle of starting up, my system spews forth a blue screen of death message that ends with:
nvstor.sys - address ffffa6000012f923e base at fffffa60012f3000, datestamp 46671a38
I have a lot of time invested on my current system configuration and would like to overcome this problem with the minimum changes.