During my previous posts regarding sudden lag / FPS drop on my computer while playing Skyrim, many recommended that I disable the Anti Aliasing
(I use ATI Sapphire Radeon HD 6850 2GB).

Why?
Would this make graphics decrease extremely noticeable?
What will happen?

Would free up your cards resources a little bit to be used on something more important. Some people hate jaggies others don't mind I personally use a 2x MSAA or 4x tops. Lowering shadows would buy you some wiggle room as well its all a matter of what you want to sacrifice.

I usually keep it at 2X. I personally cant see a difference above 4X.

Yeah depends on the game 2x doesn't do much in BF3 lots of stuck that can be jagged. Skyrim I use 2x or disabled basically if I was going to reduce something the first thing would be AA.

If you want high quality image fidelity then MSAA x8 or SSAA is the way to go, they don't just take the jagged edges of objects, they also remove a lot if not all the texture shimmering and pixel crawling when the image moves.

If you want an example, download the movie http://www.iryoku.com/smaa/#downloads and it will show different AA modes. Super sample (SSAA) is the best, just look at the shimmering on the others and the complete breaking of object detail like bars and thin lines when the image moves. FXAA is abysmal.

Very true but 8x SSAA would have my card running around 90c degrees in Skyrim unless I turned shadows like to Low.

The higher amount of MSAA (multi sampling anti-aliasing) you use, the more dedicated video memory you use. Most forms of anti-aliasing (MSAA, CSAA, SSAA to name a few) require lots of dedicated video memory more than other GPU resources. As long as your GPU has a lot of dedicated memory (1+ GB is a good start), you shouldn't notice much of a drop in frame rate. When your GPU runs out of memory, that's when you can get stuttering and low frame rates. 2x MSAA doesn't use up much memory and unless you have a very low end GPU, it'll have very little effect on your frame rate than if anti-aliasing was off. 4x MSAA takes up quite a bit more memory than 2x. 8x MSAA uses a LOT of memory. You get where I'm going.

FXAA on the other hand takes up very little GPU resources as it's a sort of post process effect on each frame/image. If you think anti-aliasing is affecting your frame rate enough, try FXAA. It doesn't look as good as MSAA in my opinion, but it causes FAR LESS stress on the GPU.

Hope this helps.

It does my concern is more temperatures when it comes to Skyrim I see 80 C and even though my card is supposed to take 105C anything above 72 makes me a little nervous. These temps are due to my barrel fan and it is very loud past 50% so I set to to that speed before gaming. With the HD Texture Pack(I have discontinued using it) 4x MSAA Shadows on Ultra and everything on max card gets to that max 80C mark. Maybe I am paranoid but I also can get a little bit of FPS dive if lots of stuff is happening at once. Also using Ugrids 7. I know I have the VRAM I don't get CTD's even if I go full on 8x SSAA all bells and whistles but the temps I would get from extended play frighten me.

As long as your video card doesn't hit 90C it's fine. Low-80s is pretty normal for a video card when it's gaming.

OK thanks for the tip the last card I had the only game I played for like 6 years was World of Warcraft and I had no clue what a GPU temp was >,<

Well, MSAA is even more heavy in DX11/deferred lighting, hence why it's so demanding in games like BF3/DX11. FXAA is the solution with such graphics tech but it really lacks the quality of MSAA. Skyrim just isn't very well optimised for MSAA and Crysis runs better at 16xMSAA so Skyrim has a problem and that is the engine is outdated and not optimised.

So, for a mid range user (GXT 560ti w/ 1 gig vram) what is the best recommendation?

4xMSAA, 2xSSAA would be a good balance because it has good image quality, plus for transparent textures tree edges, grass, plants and remove some texture shimmering,

Can you use both at the same time somehow? Or did you mean either/or? I read somewhere you can use FXAA and MSAA together or something along those lines.

Yes you can use MSAA + FXAA together because FXAA is shader based AA, so it takes jagged edges away better in pure post processing and deferred lighting. Skyrim doesn't support deferred lighting so it's really a minimal effect.

I just tried 4xMSAA w/ 4xSSAA and got very good image quality with no apparent strain on my rig.

Yes, it works well on my card but is heavy in some places. You need a mid to high end card really.

In my CCC it makes me decide between MSAA, the dreaded Adapative AA and SSAA so how would I use both MSAA and SSAA at the same time?

Not sure about AMD drivers but if you only have one setting then try SSAA. NVIDIA use SSAA for the transparency and MSAA for the AA mode. Super Sample in Crysis is just awesome, you can see it's effect on the trees because they need transparency AA to get rid of the jagged edges. In some games it's not so obvious.

GPUs can get pretty hot. Most can handle 90C pretty well. Usually they are rated for even higher than 100C as a max temp.

Thanks guys I popped the HD texture pack back on and cranked everything to Ultra other than 4x AA as opposed to 8. I changed to SSAA in CCC and wow this is the most smooth and good looking Skyrim (in combo) that I have experienced since well...ever. I should note I am also using a FOV of 70 and Ugrids to 7 with just the exterior cell buffer punched up...left out the other lines for now. Temps never exceeded 77 in an hour and with my barrel fan they will never see 90.

I don't know what my GPU temps are. How do I see that? Do I run in a window so I can look at a temperature utility? No, I run full screen. The launcher is set at Ultra High Quality which means AA is 8x and AF is 8x if memory serves, and my frame rate is never much under 50-60. Nothing is changed in the nVidia Skyrim profile — all are left on "let the program decide" except Ambient Occlusion which is on "Quality".

I use MSI afterburner not only to monitor my GPU temp but to set my fan speed higher when gaming. My card doesn't like to kick in high because it is loud but I prefer loud to frying. There are numerous applications out that will monitor and display your temps just make sure it is compatible with your card. I would assume afterburner would work fine with your 580 even if it isn't MSI brand as mine isn't either.

Shadows are the biggest performance killer. 2xMSAA / 4xMSAA is really not that demanding. Medium shadows provides a good mix of performance and looks.

There is more and more technology in graphics engines that reduces the need for anti-aliasing. Like bloom for instance, which softens bright lights and in a way works similar to anti-aliasing in that it eliminates jagged edges around these lights. Depth-of-field, weather & water effects, ambient occlusion and others have similar attributes. Higher resolutions and denser display technology reduces the need, too.

These are more or less the reasons why anti-aliasing can be left at 2x or 4x, but I would not want to turn it off completely. It still has got its place. Only the higher modes like 8x and 16x demand a lot of resources and should be avoided if possible. Instead, try turning on all effects and features of a game's graphics engine before increasing anti-aliasing above 2x.