ok so im loyal to the NCR and basically hate everyone else. however i wasnt sure what "yes man" had to offer. so i did some missions for yes man to see where it would lead me. now i had already killed mr. house for the NCR. ok but i wanted to see if i could get yes man to help me nd the NCR. so i get to the presidents visit mission (You'll know when it happens) for yes man and i complete it thinking its also for the NCR's benefit. after completing the mission everybody at hoover dam is ducking in cover and wont move but i thought it was for the time being. so as soon as yes man had me do a mission that was going to get the NCR to hate me i stopped working for him. i killed brotherhood for NCR. but my next mission for NCR is to protect the president which i had already done. when the same mission comes up (You'll know when it happens) except this time for the NCR i cant interact with any NCR troopers or imortant charcters due to the fact that anytime im in hoover dam they are all ducking in cover for know reason. the president never shows up, and my game then begins to freeze because of so much [censored] going on. these problems make me very upset figuring that fallout3 was one of my favorite games. and NV would have been if there hadnt been so many problems. i have had many other problems with the game but none restricting my gameplay like this one. i would like to complete the game under NCR however i am unable to do so. i hope these problems will be fixed with a patch because im [censored]. can anyone help?

i did that quest where u had to protect the president and mine kept freezing :L

That scene and the last march on Hoover dam both consistently suffer from terrible framerate. Ive played those about 5 times each in different playthroughs and it is occurs regardless of playtime or recent saves. It's a shame since it's meant to be one of the few memorable action scenes in the game. Really sad.

Is the 'For the Republic' quest still available? If not you may need to load an earlier save. I did both NCR and Yes Man from the same character and you will reach a point of no return where you have to complete the game following either. In my case I think I was able to tell Yes Man I killed House but when I told him about the Wildcard sidequests I then had the NCR quest path closed and had to finish the game following only using Yes Man.