here are some screenshots that will give you an idea of what is happening on my game...why this happen? http://img153.imageshack.us/g/screenshot5h.png/ go here and check..

The power lines looking jagged?
I'd hazard a guess that the amount of pixels is to small so it stretches them out thus making it look jagged and crude. Just a theory

Yes but..how I can fix that?Is it related to hi res textures?(4aces,nmc..)..I don't think so.Have I to enable AA? that look Is something horrible ! Also I see that kind of "problem" even on other textures and on enclosures around houses

Yea, that's AA, or the lack of it.

I'll try to enable/disable AA..and report the results

I did the test.If I use 2x or 4x AA the game runs smoothly but the problem isn't fixed..instead if I use 6x or 8x AA the game stutter and the problem is fixed..I am using the stutter remover which doesn't full support the new version of the game,it has a preliminary support.What should I do?wait for new vegas stutter remover full version?Also I'll install the 3gb patch when the steam compatible version comes out..Currently I am using the d3d9dll too

Ok If I play at 4x AA all run smoothly..Why if I set 8x AA I get stutter? I have a ati radeon hd 2600 xt (512mb ram but trust me,I can handle any game at max details;at least until now ),3gb ram , a Inter Core quad CPU Q6600 2,40 GHz.

I think it's the vid RAM cutting short on you

I'm getting a new card just for Skyrim. 2 gigs of Vid RAM. I want it to look top notch. TOP NOTCH!

AA = Anti Aliasing

If your screen resolution is to low, it might happen that lines, edges or other shapes look "jagged". That's totally normal. This effect is called Aliasing. It's caused by the way the images are rendered by your GPU.
Anti Aliasing helps to reduce that effect, but it cannot remove it completely. Of course 2x AA doesn't need that much GPU power. And of course the higher the AA factor is, the more GPU power is needed. So if your game starts to stutter then the AA factor is simply too high.

If you're playing in a high resolution and there is still too much aliasing then try to turn down the resolution a bit and turn AA up. It far more better for your GPU to render smaller resolutions with high AA than vice versa.

What I don't understand is..Why I get stutter when I use 8x AA just in New vegas?I can play other games such as bioshock,crysis,oblivion,dragon age( both with hi res textures etc),mass effect at max detail without any stutter! Yea I am planning to get a better video card for Skyrim/Rage I would like just to understand if is something related to my hardware or it is a game's problem

All games function differently with AA, it doesn't matter if one arguably looks better than the other. That's an older mid-range card but because most PC games are console ports you can still tweak to a sweet spot and have a playable game. Skyrim will be playable on it too, it's the same engine (although tweaked to the point where they're dropping the fact that it has gamebryo innards).

Mate,Skyrim is built on a new engine(Creation Engine right?) that has something from gamebryo as what I have understood..Btw I'll wait and decide ^^