The atikmdag error probably.

Note: most of this info is from ~april but I suppose it's still unchanged.

It is a known error for several cards in any version of Vista64.

Either turn of the secondary screen or turn of the aero theme worked for me.


I got introduced to it when AoC was launched and I installed my new computer with Ultimate Vista 64.
It's not related to anything you're doing, some have reported their system crashed before they could even pass the windows login.
Vista tries to recover from the crashed driver, sometimes manages to do so even,
but most of the time gets into a loop of recovering and crashing again, which gives you your BSOD in the end.

The error has been around since vista 64 launched and till now there hasn't been a decent solution which works for everyone.
Some fixed it by setting the gpu fan to a fixed 50% or more,
some fixed it by adding more memory,
and a lot of other things i've tried before turning off the aero theme..
(After all, it's a "new" os, I wanted it's new look,
so I tried all the other options I could find before turning off the aero theme.)

Not only ati cards have this trouble btw,
many reports have been around of people with nivida cards with the same troubles,
they just have "nvlddmkm" in stead of "atikmdag" in the error.