Help with monitors

so, my brother has a gtx 690 and his monitor is a 1080p tn monitor he wants to upgrade. he is between a 2560 x 1440 ( is it true that at this res is not necesary AA) ips 60 hz vs 1920 x 1080p tn 3d 120hz wich one is better for gaming 

Matter of opinion. I'm getting myself a 2560x1440 ASUS PB278Q. I happen to like more of a cinematic experience and I find 60hz to be sufficient for my needs. I play a larger library of games which includes RTS (no, not starcraft) style games. I can understand why people would want a 120-144hz panel if they played mostly FPS games, or maybe racing games. I've never had trouble scoring kills in any FPS game at 60hz. However, 120hz panels do cost less than 1440p monitors. I'd sway to 1440p if my budget permitted it. I just think it is better for general use as much as gaming. You've got the GPU horsepower to back it up.

budget is not a problem, the only thing is that in argentina we only get dell for that resolution. he was thinking about getting the U2713HM or the U2711 this are the only monitors with high res that dell bring's to argentina. 

the only problem is that he is not sure of the performance he will get,  that's why he was asking about the AA. because he saw this video:

another thing the ghosting and time response is a problem?

With a GTX690, performance shouldn't be an issue, you're going to get playable frames. You could use fxaa which is a less demanding type of AA, it works really well at that resolution. Only thing is, I'm not really a fan of Dell. Personally, I would still sway toward 1440p, I just know that the Dell model has more complaints/issues than the ASUS. You're always taking a risk when you buy computer hardware, I suppose!