X11 please, ScryptN is too heavy on GPUs and there have been many reports of it destroying GPUs already.
I lost a AMD 7950 while mining with vertminer. Not a good choice.
If you mine without any overclocking, there is no risks to the GPU. Any miner has the potential to damage his gpu's.
I have mined many scrpyt algos without any problems. You just need a certain level of caution with any scrypt/algo.
The latest drivers for most cards have failsafes in case your vram overheats. My rigs auto shutdown when a certain temp is exceeded.
Certain flash bios disable that feature.
It has nothing to do with overclocking your gpu and everything to do with the type of algo being used. N-Scrypt destroys gpus.. not disputable.
Stick around though.. there is a lot of information for miners that are just starting to mine. this being one tidbit of info.