Sounds like your laptops graphic card is entering a powersave mode for some reason. Do you have your laptop plugged in or just running in battery? Try going into your graphic card's settings and turn off its mobile settings and try it again. That should solve your problem when running the game.
I'm not sure if it's a bug or not, but from what Merk says, it doesn't seem that you are supposed to be able to get his quest to kill the Hubologist or fight lenny if youve already delivered to him the papers from Dr. Henry, either that or he should have alternate text to them instead of the...
When in the NCR, Merk sometimes still doesn't show up with his bodyguards and I am still getting stuck in the ring with Lenny after using the mutant serum on him.