Originally Posted by darklordjames
"but if you regularly play any games that are sub 720p (like cod), then you'll be scaling on the Xbox to 720p anyway"
Not in relation to the topic. To over-simplify: Sub-720p games scale internally to the game, then overlay the 720p HUD/interface, then hand off to the OS. In the case of something like COD, the 600p render in effect gets scaled twice when the 360 outputs 1080p. Once from 600p to 720p inside the game. Then a second time from 720p to 1080p at the OS level. It does not skip directly from 600p to 1080p as you implied.
"Native res on console never changes,"Rarely
changes, not "never".
Not true. Every game is different, but more recent Cods go straight from its res (600p) to whatever you set - 720p, 1080p, etc. There is no higher res UI overlay in this case. For reference: http://forum.beyond3d.com/showthread.php?t=46241
In upscaling to 1080p, some games may first scale to 720p in software before the GPU scales to a 1080p output. e.g. RR6, SCIV, VF5, CoD4, H3, TR:L...
Some games let the GPU handle the scaling to 1080p directly from the arbitrary resolution. e.g. MotoGP 06, PGR3, ESIV:O...
You can even see the switch happen to 600p if the OS UI pops up while loading (like a friend logging in) - if it happens when the res switch does, it'll blink out and come back blurrier, because the internal resolution of even the UI subsystem has dropped.
So with a 1080p TV, in those games that scale directly to the res you set - if you set 1080p, the 360 scales once, to 1080p. If you set to 720p - the 360 scales to 720p, and your TV scales to 1080p. Double scaling isn't great for image quality or lag.
But if you have a TV that can scale 720p-1080p faster than the 360 (you'll have to test it) - if you put in a 720p native game, the 360 doesn't have to scale at all, the TV will do it faster, and you'll save a few ms of lag.