For the computer part, this is what I was referencing: "No, because last time I checked, you would need a computer to put that drive in."
This implies that someone who buys a PS3/Xbox 360 doesn't have a computer. Think about it, if they have a 42 inch HD Plasma and a PS3/Xbox 360, I think they would have a computer.
Pixels are bigger on the 42, you can see more detail on the 800x600 18inch res.
Notice how I am not an uninformed average customer? I would, in fact, rather play on a smaller screen.
This is an utter fallacy. You absolutely see less detail on an 800x600 18in screen vs. a 16:9 42in HDTV screen at 1920x1080. How can you see
more detail in a screen with not only less viewing space, but less resolution? That's like saying you can see more detail in a photo taken with a 2 megapixel camera vs an 8 megapixel camera, it's all backwards.
Also, borrowing your own argument about the '100x100px' image, I'd much rather see it on a 42in. You want to know why? Because accordingly, the pixels will be bigger, the scalability will be higher and therefore I should expect to see the image far more clearly than on a dingy little 800x600 screen.
The physical size of the screen is also a pretty moot point when you're scaling everything else. Now to the crux of your argument - P/I or rather, PPI (Pixels per inch, for those of you playing at home). To prove how little of a difference the actual PPI makes, below is the PPI of the two examples we seem to be using.
PPI is calculated by the following:
Diagonal Resolution = Square root (Width
2+ height
2)
Pixels Per Inch = Diagonal Resolution / Diagonal Screen Size
The MATHS!
800x600 18inch
Diagonal Resolution gives us 1000 after resolving: SqR(800x800 + 600x600), which gives us 1000 / 18 for the PPI, or 55.555555 recurring ad infinitum.
1920x1080 42inch
Diagonal Resolution gives us 2202.90717 after resolving: SqR(1920x1920 + 1080x1080), which gives us 2202.90717 / 42 for the PPI, or 52.4501707.
Hmm. A difference of...wow...3 PPI? That is a drop in the ocean when you consider PPI of screens can range in the hundreds. Drop the 42in down to a 40in and the difference becomes .5 of a PPI. Seriously, consider what you're trading that measly amount for in terms of clarity, detail, visibility and screen real-estate.
I know which one I'd prefer.
[EDIT]
Btw, my screen is a 20 inch CRT capable of 1600x1200
Oh my goodness, I feel sorry for your eyes. CRTs are not only power-hungry monsters and have terrible ergonomics, but they'll absolutely trash your eyesight. Especially when playing games. I hope the only reason you're still holding onto that beast is because you are a serious artist/digital graphics person and need it for the colour reproduction.
[/EDIT]
