Reality is this:
When you are displaying a PC via HDMI on a Mitsubishi DLP TV, after overscan, your Mitsubishi DLP is a 1824x1026ish monitor… overscan is there both because of being projection and being broadcast tech based.
Q: Can I adjust out the overscan on a Mitsubishi TV to get the entire 1920x1080 fit to the screen so I can set my PC to that resolution?
A: NO…. the service menu doesn’t allow that adjustment, only keystone (edge geometry), and centering.. the remote ‘format’ button will allow you to set ‘reduce’ mode that puts the whole 1920x1080 on the screen, but it UNDERSCANs it dramatically leaving a few inches around the entire image… there is no 1:1 adjustment like you see on direct display sets like LED / LCD.
Q: is it really that bad a problem?
A: IMO, No … especially if you have an Nvidia card… here’s what happens with PC content:
1- you start with a content file encoded with H.264 or whatever
2- you have a codec installed that decodes that stream in conjunction with your Nvidia video card
3- Nvidia cards have PureHD which is basically a hardware decode engine that takes your content stream (I'll remind you that video cards are very high performance PCs these days)... decodes it on the video card, AND does high performance image enhancement on the fly. ATI and Intel have this also, but after watching the driver race for a decade, I’ll take the Nvidia image any day.
4- it does that work and then combines that with high performance SCALING to match whatever display size you have selected by sizing your vid player window or making it full screen ... this is an important point... so it takes 1920x1080 content, enhances it, does a very high performance scaling to 1824x1026 or whatever you have set, then sends it to the TV
5- your TV displays a 1:1 pixel view of the 1824x1026 enhanced image, eliminating issues with projection scaling etc.
I like the 1080 and 720 output of my Mitsu in this scenario, a lot... and I also like the projection / film like quality of playback which you don't get with the harshness of an LCD / LED, but that's a whole other discussion.
Lastly, I'll point out that a lot of HD content is still 720 anyway and is thus getting upsampled by the TV, Player, or PC anyway so I'm not really uptight about getting my full 1080 1:1....
I have a lot of 720 and 1080 and 1080 bluray content that I have compared on this setup vs a regular 1080 LED and I'll take the Mitsu every time... also I'll point out that the Nvidia 720 upscale is so good I am unable to tell the difference from 1080 bluray almost all of the time.