For anyone with a Nvidia 600 series card suffering RED SCREEN OF DEATH (RSOD) issues. Here is how I resolved it. (Also, I had also just upgraded monitors to DELL Brand and installed the software that came with them - this may be important...see below)
After much research nothing I found seemed to fall into the same category of faults as what I was having. I.E. the main cause is widely reported as a software monitoring issue involving GPU TWEAK, or GPU -Z, or any other ASUS software. But I had none of these (Except Asus AI) installed - but I uninstalled AI anyway, without sucess.
I had no success in updating my ASUS BIOS.
I had limited success upgrading Nvidia drivers to 306.23. These drivers certainly allowed me to boot into the desktop environment but it was a lottery as to how long the system would last before the RSOD returned
RED SCREEN mainly occurred at startup just after logging in, leaving me no-where to go...couldn’t even CTRL-ALT-DELETE. What I found though was that if I adjusted my background wallpaper to cycle on a short period, i.e. only 60 seconds, then when the wallpaper changed (automatically after 60 seconds this seemed to force the graphics card out of it's RSOD and I would then be able to operate normally. The problem only returned after a reboot of the system.
The ultimate solution came in the form of a little known report about a program called softOSD, from EnTech Taiwan. It appears this got installed when I installed my DELL monitor drivers that came on the installation disk. http://www.entechtaiwan.com/lib/softosd.shtm
Some people have reported that it's removal has been successful for them so I uninstalled and VIOLA - NO MORE RSOD!
Points to note...at the end of the uninstallation process I was asked to confirm the deletion of two files that were installed either before or after the softOSD software was installed. One was the sodtOSD .exe, which I selected for deletion.
The other however was a file called se64a.sys located in C:\Windows\System32\drivers\se64a.sys
IMPORTANT: Sometimes this se64a.sys file is disguised in other locations as a virus/trojan/spyware, especially if you find it located in these locations as described in the pcmaxutilities link above
•"C:\Program Files\Common Files\se64a.sys"
Otherwise, if it appears in the location C:\Windows\System32\drivers\se64a.sys then it is a Windows system file that should indeed be there - SO I DID NOT DELETE THIS FILE when the uninstall asked me.
DISCLAIMER: I am certainly no wizard when it comes to these things so treat this post accordingly. This info is from my research and experience only.
I found that uninstalling softOSD via ADD/Remove Programs...or via the uninstall application found in the C:\Program Files (x86)\softOSD folder, worked for me.