Problem outputting PC to LCD HDTV.

[KieranMurphy]

I bought myself a 32" LCD TV recently (a cheap and probably not very good one, but it's what I can afford).

I have 2 DVI outputs on my graphics card and instead of hooking one up to a second monitor as I do, I thought I'd experiment with hooking it up to the new TV instead, to see what playing DVDs and videos would be like on it. It's a DVI output, but I'm running a VGA cable through a converter and into the VGA input on the TV.

It's capable of displaying 720p, so I set that resolution and it's displaying a crisp clear picture, as if it's in native resolution. However, it seems that part of the picture is missing. When I maximise application windows running on the LCD TV, the bottom and right are missing, as if they're off screen. I tried moving and resizing the LCD TV display via the TV remote, but it doesn't help. After a bit of experimenting I seem to have a display that actually measures 1200x700 pixels, so the bottom 20 and right-hand 80 are invisible, as if they're off-screen.

According to the TV documentation, the LCD has a resolution of 1366x768, so where's the rest of my picture gone? I run my XBox in 720p mode on the same TV and I haven't noticed any similar problems with part of the picture missing. Is it just a crap TV that can't handle input from a PC or am I missing something?


KM.

 

[Pako]

Can you accept component inputs on your TV? DVI->HD Component Adapter from ATI (assuming you have a ATI card) has dip switches for the different modes, i.e. 720p specifically. Then you set the resolution via the ATI driver and your set.

nvidia should be similar.

 

[KieranMurphy]

Can you accept component inputs on your TV? DVI->HD Component Adapter from ATI (assuming you have a ATI card) has dip switches for the different modes, i.e. 720p specifically. Then you set the resolution via the ATI driver and your set.

nvidia should be similar.

Yes, the Xbox 360 is hooked up to the TV via the component inputs. Are you saying there's some sort of DVI to component cables you can get for graphics cards?


KM.

 

[Pako]

Yep

http://slo.craigslist.org/sys/235057226.html

 

[TB]

I bought myself a 32" LCD TV recently <snip> I thought I'd experiment with hooking it up to the new TV instead

I did the exact same thing tonight. I am just running a male-male VGA extension cable. Is that an option for you, or does it need to be a DVI output?

After reading the Interceptor's post, I also had to change me resolution to 1024X768 for it to display decent.

 

[the Interceptor]

You should play with different resolutions. I have the exact same setup at home (cheap LCD-TV on PC), and it took me some tries to find the optimal settings. My panel has a native resolution of 1366x768. The only mode it accepts natively is 1280x768 though. So, I have black stripes on the left and the right of the picture, which don't really disturb me.
Anyway, if I set the PC to a higher resolution, the TV just displays the upper left corner of the pixels and cuts the right and the lower part. It still looks pixel perfect, because every transmitted pixel hits a native pixel on the screen, for the price of not getting a full picture. You should try some lower resolutions to see what the TV will display then. You can easily see if it's pixel per pixel, or if the TV will start to interpolate. This way, you should be able to find a resolution that fits.

Even like this, HDTV looks great by the way.

Regards
the Interceptor

 

[KieranMurphy]

I did the exact same thing tonight. I am just running a male-male VGA extension cable. Is that an option for you, or does it need to be a DVI output?

My graphics card has 2 DVI outputs so I'm, using a DVI-VGA converter and then just using a standard VGA cable to hook it up to the VGA input on the TV.

After reading the Interceptor's post, I also had to change me resolution to 1024X768 for it to display decent.

I might try experimenting with different resolutions then. I went for 1280x720 because I assumed that would be the obvious resolution to run a 720p TV in. I don't want to have to run in a non-native resolution. It's one of those things that bug me - seeing people running LCD monitors that should be in 1280x1024 but are instead in 1024x768 and they can't even tell the difference!

edit: It's working fine now in 1024x768 mode. It's in native resolution, there's just black bars at the sides. I'd ideally like to run it at a 16:9 resolution though to take advantage of the whole screen - playing DVDs and 16:9 aspect ratio videos is going to end up with black bars at the sides AND top/bottom. 1280x768 doesn't work at all - about a quarter of the picture is covering the whole screen and it's all green.

edit again: My eyes are playing tricks on me. I've been switching back and forth between resolutions the past few minutes and although it's not taking advantage of the whole screen, the 1024x768 mode looks far better than the 1280x720 which means that the 1280x720 wasn't running in native resolution at all.

http://slo.craigslist.org/sys/235057226.html

That takes a standard DVI ouput and converts it to a component signal, right? Is there any reason why something like that wouldn't work with my nVidia graphics card?

Do you think would using a DVI-HDMI connection make any difference at all?

Thanks for the advice guys, I'm going to do a bit of experimenting today and if need to, I'll pop into my local TV or PC store to see if I can pick up something similar to what Pako sugested.


KM.

 

[Seanman]

Try looking in the TV's display settings. Usually, there is an option where you can choose to stretch the picture, display it normally, crop out the side bars, or crop out the bottom bars.

 

[KieranMurphy]

Try looking in the TV's display settings. Usually, there is an option where you can choose to stretch the picture, display it normally, crop out the side bars, or crop out the bottom bars.

I tried the various options, but it was no use.

My graphics card actually has a third output (not a DVI or VGA, a little circular one with lots of pins) and a supplied adapter for connecting S-Video, composite video and component video, but I tried it with an S-video cable I have here and the picture quality is awful. All blurred and useless.

Anyway, I had a look at the manual (why didn't I think of that in the first place!) and 1280x720 isn't one of the supported VGA inputs. None of the supported VGA inputs are widescreen (640x480, 800x600, 1024x768 and 1280x1024).


KM.