> I mean, does it look any different from frame quadrupling? I'm just trying to grasp
> how they will differ visually on a 40" LED TV. Does one look better than the other?
> How do they look different? Or do the come to the same place only in different
The way it really works is a 240p image would look super small on a 1080p set. Upscaling means the image size is increased. Your TV has ways to do this but it doesn't do it in a smart or uniform way so you see a bigger representation of your small image which shows all the problems at a magnified level. The image is usually stretched or compress in so way.
Scaling through a device like the framemeister or OSSC can give you a better image because they handle scaling better and are able to support more resolutions. The double/triple/quadruple wording simply means "integer scaling". Example, you take your 240p image and quadruple it, this gives you a 960p image. The upscaler in your TV (most of them) would simple stretch the image or try to fill the screen by converting it to the closest match or simply not display it at all depending on what modes it supports. The framemeister will allow you to retain the aspect ratio and place black bars on the top/bottom/left/right to fill the screen instead of stretching the image itself.
To fill the screen through a framemeister with 240p, you'd pick a 5x resolution to retain the original aspect ratio or you have the option to set custom ranges inbetween. The idea is that it gives you freedom to change the resolution, upscaling and aspect ratio, while also letting you crop/stretch, etc the image manually creating your own custom type of display scenario that works best for your TV. So basically it lets you fine tune things to work best and gives you more compatibility options for your specific TV.