Problem driving External widescreen from Mobility 7500

neilhand · Feb 10, 2006, 12:35 PM

I am trying to drive an external Sharp LCD TV using the Mobility 7500.

Using the Omega drives I am able to select 1280x720 output resolution, however this is sensed by the monitor as 1280x1024, causing the image to appear scaled. However the display area represented is 1280x720 - just apearring letterboxed within the 1280x1024.

I have previously driven the LCD using an S3 embedded soluton without problem, so i assume it is the driver setup itself rather than the

If anyone can provide any insight it would be greatly appreciated.

swimtech · Feb 12, 2006, 04:50 PM

Is your Sharp TV a 4:3 (NTSC TV standard 'square' type) or a 16:9 (NTSC TV widescreen HDTV ratio) display, and what is the native resolution of the Sharp LCD TV? You could post back the model number of the TV as well if you don't mind.

Sounds like you're trying to display a widescreen (16:9) image from your computer onto a standard size TV (4:3). In that case, the letterboxing you are seeing on your TV would be normal - it's doing what you have asked it to do. As long as the video within the letterboxed area looks normal - without stretching of objects horizontally - sounds like it's working as it should. The S3 solution you were using before may actually not have been sending it out properly even though you were happy with it then.

I hope I'm not missing something though - let me know if I am misinterpreting what you are describing...

neilhand · Feb 13, 2006, 01:59 PM

The TV is a 16:9 Sharp Aquos display (37GD4U). The Native resolution is actually 1366x768, but it also will take native 720p (1280x720) and does a nice job of scaling without too much artifacting.

The problem seems to be that even though the Mobility is set to output 1280x720, rather than driving the native resolution out the back of the device, it seems to be driving 1280x1024 and then letter boxing it. The Sharp then scales this down to fit the fill 4:3 image in the screen.

I can (and currently do) zoom on the portion of the image that i am interested in to fill the screen, but all the up and down scaling makes things less then steller quality (compared to what it looked like driven by the S3 embedded solution used previously).

Just in case it is of relevance, the device driving the display is a laptop (4:3 aspect) with the LCD turned off, and only driving the sharp (via VGA connector).

Thanks for your help.

cpt.pepper · Mar 7, 2006, 01:53 PM

I want to use my TV as a monitor when I play music from the lap-top, but I can`t make it work. I have a cable from the S-video on the lap-top to the scart-conector on the TV, and expected something to show up on the AV-channel on the TV...but no... Do I need an extra driver for this? I have selected dual monitors on the PC.... As you probably understand, I don`t have much knowledge on the issue....
Anyone who can help me?

cpt.pepper

bencip19 · Oct 28, 2006, 02:56 PM

Hi,

I'm spamming this post pretty much in all the threads where people are having issues dirving external widescreens from their Mobility Radeon card. Sorry if this is against the rules; there are so many threads to sort through for a person who searches, I figure I should put MY answer in as many of the places (and they're all appropriate) as I can.

I was having the same issue with my Mobility Radeon 7500 and Widescreen. I got it to work (with quite a bit of effort), and just wrote up a webpage summary and posted it to my personal website.

I hope it's OK to link; best to get the information (and pictures) off there. All the real credit goes to those who wrote ModTool.

http://www.quickowl.com/Services/Hardware/Mobility Radeon WS/

Thanks!
Ben