How do I increase the resolution of a laptop screen more than it supports?

Sometimes increasing resolution is useful (even though it does reduce quality). If a dialog's height is hard-coded to 800px it'll be off the bottom of the screen, and there's very little way to see it. On a 1366x768 monitor it's less of an issue, but on a 1024x600 netbook I hit this issue all the time. Maybe you have a higher resolution external monitor and you want windows to appear the same physical size on both screens - there are lots of reasons.

You can change the resolution to above native res on Linux using the following command:

xrandr --output LVDS1 --scale 1.25x1.25

I find that a scale of 1.25 is on the edge of usability, probably 1.2 is more sensible. On your laptop, the output name may be different - but a quick google for XRandr will show you how to use it.

Having said that - the command worked perfectly on my Ubuntu 10.04-based netbook, but for me, on 12.04 (with gnome-panel) it changes the resolution but the mouse is still locked to the old area of the screen. It appears to be a regression, and there is a fix below so hopefully it will be fixed soon:

https://bugs.launchpad.net/ubuntu/+source/xorg-server/+bug/883319

Use the xrandr command. For example: My native res is 1680×1050.

If I type in terminal:

xrandr --output LVDS --panning 1920x1200 --scale 1.1428571429x1.1428571429

I will get perfectly good 1920×1200 resolution (it's 16:10, as my screen is) but, as an earlier answer suggested, this creates an oversized desktop. I need to pan around because the whole screen cannot be shown at once, you just don't have enough pixels, that's why it's your max res. scale # you get by dividing your desired res with current res (for me 1920/1680 therefore 1.1428571429).

If you wanted full HD (e.g., 1920×1080 for your 16:9 display) you'd type in terminal:

xrandr --output LVDS --panning 1920x1080 --scale 1.4055636896x1.4055636896

We got your scale by dividing 1920 (desired) by 1366 (current/native). If LVDS doesn't work then try LVDS1 or type xrandr and see which one is connected. Could be VGA1 or CRT, but if it's laptop it's most likely LVDS or LVDS1.

It would not make sense to increase output resolution more than the screen is capable of displaying.

In best case it would have to rescale the output back to its native resolution (it must show is using a fixed number of pixels), which would require processing power and give you a worse result than just using the native resolution (most likely 1366x768, not 1399) due to interpolation errors.

In worst case it would just fail and not give you an image at all.

Sometimes it makes sense to send a resolution lower than the native resolution, e.g. for games where the graphics adapter doesn't have the power to render it smoothly at the native resolution, and use interpolation to show it on the full screen, but this should be avoided.

For completeness: to increase the resolution on your laptop you would have to buy a new laptop panel that is compatible. This is most likely not available, unless you are in real luck and your laptop is part of a series where a higher resolution model is available. It would still be a bit of a gamble to find a new panel unless you can find trustworthy verification of the specific panel model working with your specific laptop model.

If this is not what you mean by your question, you need to clarify.