Same here.

Does your monitor have the ability to disable its own scaling? If so, that is the key. Part of what fixed aspect ratio scaling does is tell the monitor to turn off its own scaling. Since my monitor lacks that option and always scales, its does not work.

My monitor has that ability, but I always keep it on "aspect correct".

Actually I also have a 1280x1024 monitor which does not have the ability to turn off scaling - it stretches EVERYTHING to 5:4. And the fixed aspect ratio scaling still works perfectly on it.

Having your GPU do the scaling doesn't shut anything in your monitor off or whatever, it just scales the image and presents it to your monitor at your native res. There is no scaling to shut off because the monitor is receiving a native image.

It will still be a bit blurry though, as it is still being scaled, just by the GPU.

Oh, yes it does. With aspect ratio scaling you would only have your screen filled if the res you're upscaling has the same aspect ratio as your native resolution. Otherwise there'd be black bars.
On "normal" LCDs the driver dictates the scaling behaviour to adopt.

Nobody is saying that aspect ratio scaling will fill your widescreen monitor with a 4:3 image. However if this is turned on in the GPU drivers, the black bars should be added by the video card and not the monitor. The monitor should see it's native widescreen resolution.

I'm not talking about fixed aspect ratio, I know what that is and mentioned it before. That's an option, but there is a general "use nVidia scaling rather than my monitor's" option as well with no fixed aspect ratio. That should present the monitor with a native resolution to display, even though it is still being scaled by the GPU.

Forgive me, I misunderstood you then. And yes, I agree.

It doesn't mean just blurry textures, it also means pixellated textures.

Texture resolution is very much related to your screen resolution, in the sense that the relative size of the two does in fact matter. If you take the same 3D scene and render it at different resolutions, the percentage of the screen taken up by a given texture is the same, but the number of pixels it takes up is not. Once the resolution gets so high that the texture takes up more pixels than it itself has defined, it starts to pixellate. If the rendering engine uses interpolation, it also starts to blur. Look at the image PhoenixWright posted to see both effects. Especially on the ground in the foreground, and on the column to the left of the player character.

Of course, whether or not one minds that the individual texture pixels take up multiple screen pixels, is wholly a matter of personal taste. Personally, I find it jarring to have essentially two different pixel sizes on screen at the same time. I think it looks better when the texture resolution and the screen resolution match.

In my experiance, pixelated textures effectively disappeared almost as soon as 3D acceleration appeared - they're blurred out by bilinear/trilinear/etc filtering.

If you look really close at the attached screenshot you'll see remnants of pixelation, but it's so blurry that you really do have to look for the pixels to distinguish them. Won't notice it when running around and shooting, that's for certain.

sorry but it's nonsense. in 3d space there isn't something like a texture -> screen resolution correlation because the 3d object are moving and rendered with different perspection. if you ever played DooM you know that at every resolution you play if you get close to a wall pixels are 100 times bigger than the on-screen pixels.
Texture resolution and screen resolution matches only for HUD elements.

Actually, that happens when it runs on the N64 too. The N64 always used really low res textures and lots of interpolation. Those textures looked like that on the N64.

Naturally, any texture will pixellate if you zoom in far enough. The reason it's so obvious in Doom is that it uses extremely lo-res textures, so that even in the smallest resolutions, the wall textures pixellate. Such were the limitations of the hardware back then. There was no 3D acceleration, and the game had to be able to run with no more than 4MB of RAM. This put sharp limitations on texture sizes, both because they had to fit into a very small memory space, and because there was not a lot of processing power available for rendering.
Look again at PhoenixWright's screenshot. The HUD elements are heavily pixellated too.

And the texture resolution doesn't have to match the screen resolution, unless the texture takes up the entire screen. It just has to be big enough not to pixellate at the size you will normally see it at. Again, if you stick your face in the wall, the wall texture will pixellate no matter what you do, but then it's not meant to be seen that close.

The only time a texture will not suffer some kind of problems is when you look at it squarely from exactly the right distance so that it matches up with the rendering resolution 1:1. Further away and you'll get downscaling type problems, closer and you'll get pixellation/blurring. He meant that the only time there is a match is HUD elements at native resolution. Textures will always be viewed at different distances and angles.

Not if the game swaps in ultra-high res textures up close :)