PowerMac to HDTV fullscreen?

[Mechcozmo]

My friend has a dual 1.42 PowerMac G4, connected to his HDTV via DVI->HDMI. The Mac correctly identifies the TV and sets 720p as the highest resolution it is able to support. (1080i actually is, but doesn't look good and the video card likes 720p)

It has a Radeon 9000 Pro. It is running Tiger. But it doesn't fill the entire screen. With overscan, it fills up TOO MUCH of the screen. We want it to fill right to the border of the screen without cutting off any. That way, iTunes, DVD Player, etc. can be used without pain.

Is there a way to do this?

 

[balamw]

Try SwitchResX. It should allow you to add or set the resolution of the display to the native resolution of your display, eliminating the black bars or excess.

B

 

[Mechcozmo]

Try SwitchResX. It should allow you to add or set the resolution of the display to the native resolution of your display, eliminating the black bars or excess.

B

We did try that. But 1290x720 is the right resolution. (720p) It just doesn't fill the screen.

Are you suggesting we set it to something like 1300x750 and see if it fills the screen? That would involve scaling any videos a bit...

 

[robbieduncan]

The problem is likely to be that the TV is passing everything through it's scaler even when it shouldn't need to. More or less all HDTVs seem to do this. With some messing around you can normally get 1:1 pixel mappings by running at strange resolutions.

 

[balamw]

We did try that. But 1290x720 is the right resolution. (720p) It just doesn't fill the screen.

I presume you meant 1280x720. (At least that claims to be the native res of my 720p TV).

I don't have a DVI Mac to play with my HDTV, but wonder if it might be a refresh rate issue. Are you trying 1280x720 @ 60 Hz? > 60 Hz might be too fast for the display and so it scales it down to accomodate.

Since my HDMI port is already connected to a HDDirecTivo, I may just try and play with the VGA port to see what I can get out of it.

B

 

[Mechcozmo]

I presume you meant 1280x720. (At least that claims to be the native res of my 720p TV).

I don't have a DVI Mac to play with my HDTV, but wonder if it might be a refresh rate issue. Are you trying 1280x720 @ 60 Hz? > 60 Hz might be too fast for the display and so it scales it down to accomodate.

Since my HDMI port is already connected to a HDDirecTivo, I may just try and play with the VGA port to see what I can get out of it.

B

Er... yes, you are right on that resolution. My mistake.

No, 60 Hz is the refresh rate on NTSC TVs. Can't change it. :-\

The problem is likely to be that the TV is passing everything through it's scaler even when it shouldn't need to. More or less all HDTVs seem to do this. With some messing around you can normally get 1:1 pixel mappings by running at strange resolutions.

How exactly would we go about doing this? Would we use "SwitchResX"? Where should we start? What ratios do we keep?

Thanks for the information about the scaler though.