can a t42 drive a HD beamer?

[schmaud]

Hi,
I have a t42 (non p) with an XGA screen ( the ati 7xxx GPU not the 9xxx)
Is it possible to use this device to drive a beamer with

- 1280*800
or
-1920*1080
resolution?

I woudl guess I would have to configure this as a second external screen, but I am not sure.

application will be showing digital photos, but no HD-video. We will watch a DVD ocationally.

thanks in advance

r.

[aceo07]

The ati 7xxx should be able to do 2048x1536 on the external vga port.

You have a really nice beamer ( I assume a 'beamer' is the same as a 'projector') if it can do 1920x1080.

[awolfe63]

I have a T42 (in a minidock - but that should not matter other than having 2 external outputs) driving both a 1280x1024 LCD and my 1080i HDTV.

[basketb]

Make sure you use the "omega driver". Google it, if you haven't heard of it before.

[awolfe63]

I didn't need to. I think I just needed the right monitor driver. I'll check my machine at home.

[sjthinkpader]

There are a lot written on the web on how to connect PC to a HDTV.

At first HDMI seemed the best connection method. But the interface cause Windows to set 1280x720 resolution for a native 1366x768 720p TV. So the image is missing a border.

This is caused by most HDMI interface chips expecting overscan from DVD player, cable box etc. So it reports 1280x720 to the PC and remap the incoming image.

TVs with VGA and DVI input does seem to report the correct resolution to the PC but TVs with these interfaces are far and in between.

There are software that can change the PC output to better fit the TV but these are certainly not consumer friendly.

Currently I am using a A31p with DVI-HDMI cable and outputting 1280x720 to a 1366x768 TV. It is missing a border. The older A22p/A30p/A31p are perfect as slideshow machine. Sometime I use it as DVD player when all else failed to play certain disc.

[sjthinkpader]

...my 1080i HDTV.

1080i is only a legacy mode in any HDTV today since none really uses interlaced beam scanning anymore. They should be either native 720p or 1080p.

[awolfe63]

I'm not sure what that means. Lots of content is broadcast and recorded in 1080i. HD video cameras use 1080i. Many devices including upscaling DVD players provide 1080i as their highest resolution output.

Almost all HDTV's take 1080i input - then scale and deinterlace it for display. Most TV's made more than 2 years ago have it as their highest resolution input. It happens to be the highest input level for my 65" Sharp LCD TV.

[sjthinkpader]

That means there are a lot of conversion on the source end and the display end to use 1080i. The display device is either 720 or 1080 horizontal lines today (most 720p is actually 768 native).

DVD recording is not recorded in interlaced mode. They are in serial mode.

Certainly DLP, plasma or LCD displays do not use interlaced scanning to put up an image.

Manufacturers only include interlaced mode in equipment to service those few 1080i CRT that were built in the past twenty years. The rest are all done by conversion in interface chips.

If you TV has 720 lines (768 native), using 1080i doesn't increase your image quality. If you TV has 1080 lines, there are even less reason to use 1080i.

[awolfe63]

Most TV's built before late 2006 will only accept 480i, 480p, 720p, and 1080i. Every HD cable set top that I know of only supports these formats. NBC, PBS and CBS broadcast in 1080i as do most HD cable networks.

This content needs to be scaled up to 1080p to be displayed on a 1920x1080 LCD or plasma. Either the graphics chip can do it or the TV can do it. In most cases, the TV will do a better job. For many TV's it is the only choice.

Are you suggesting that 1080i source material should be deinteralced and downscaled to 720p, sent to the TV, then upscaled again to display resolution?

[sjthinkpader]

There are no source material in 1080i, only interface. DVD is only 480 lines before up conversion.

If one has a 1080 line display, of course it is best to get 1080p source material such as Blueray player or PS3. In the absence of that, 720p work just as well.

Both cable and DBS (direct broadcast satellite) HD are only 720p. When you set the setup box to 1080i, the box does the upconversion to 1080i. The 1080p TV has capability to up convert from 720p. When a 1080p TV receives 1080i signal, it has to store the 1st pass and the interlaced 2nd pass before it can use the frame anyway.

1080i today has no source material or display device. It is only an interface standard. It gets manipulated both in the setop box and the display device.

[awolfe63]

There are no source material in 1080i

Well you are wrong - but I don't see the point in debating it further.


"Today, over 70 NBC owned and affiliated stations are broadcasting digital television. We currently broadcast certain series and movies in the 1080i HD format, providing the highest resolution possible" (under broadcast standards)
http://www.nbc.com/Footer/HDTV/


FOX 720p WDAF 720p
CBS 1080i KCTV 1080i
ABC 720p KMBC 1080i
PBS 1080i KCPT 1080i
CW 1080i KCWE 1080i
NBC 1080i KSHB 1080i
MYTV 1080i KSMO 1080i

http://groups.google.com/group/alt.vide ... d3525d3493


http://en.wikipedia.org/wiki/ATSC_Standards
http://en.wikipedia.org/wiki/HDTV#Broad ... iderations

[sjthinkpader]

...

Well you are wrong - but I don't see the point in debating it further.

That's convenient. But that's ok, I've known to be wrong.

That means there are a lot of conversion on the source end and the display end to use 1080i. ....