I've found a SOLID fix for this problem.
1) Delete ALL Nvidia drivers.
2) RollBack or UPdate your current LAN drivers, especially if you use an ASUS mobo.
3) Restart
4) Windows will automatically install some drivers to your system for your current graphics card if you use Win 7
This is normal
4a) Run CCleaner <--- See below
4b) Run Driver Cleaner from Guru3D.. <--- See below
5) Install the current Nvidia drivers. At the time of this post it is version 197.** released this month.
6) Restart
7) If no BSOD after restart, Set SLI settings and test.
8) After restart test system for BSOD boot up and run screens.
I highly recommend running a few free programs to help with this:
Nova Bench -- Free system test. Run it often.
NovaBench - Free Download
CCleaner -- Gets rid of your old driver files and reboots for you.. Extremely important for removing Nvidia files.
CCleaner - PC Optimization and Cleaning - Free Download.
Driver Cleaner: Deletes all left over Driver files, specific to Nvida, Creative labs, ATI..
Guru3D - Driver Sweeper download from Guru3D.com
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