DVI on PC to HDMI, screen size to big

sutty

Hello all, I got a DVI to HD cable last night and hooked the PC up to the TV. I have a Radeon X1800xl. When I first hooked it up. I could get into a 1080i mode (runs at 30MHz) 60MHz would just not disply. I have a JVC LT32DS6 LCD TV. Which is meant to be able to do 1080p Standurd at 60MHz. Even the controle panel on the Det drivers picks this up as the Max setting of the TV. The second problem I had, was that the display was always to large when using the PC to HDMI. IE: in all drections its off by about the leanth of the start butten at what ever res you select.

So thinking it may be a driver issue (they where about 8 months old at that stage) I upgraded them to the latest on the ATI site. Now the TV will only go to a 720p Standurd. This time the screen size is correct. But when ever I try go to a 1080p or 1080i setting. It wont desply. Has anyone seen this problem before? Oh and the cable is 1080p standurd. I seen one person in an other forum with the same problem on a ATI card as well. But no fix was given on the site. So any ideas would be a great help.

ps... You cant change the width or hight of the screen when outputing to the HDMI. Only when in a VGA mode on the drivers. I went through both the TV's settings and the cards drivers. But it has me a bit stumpped.

ffocused

did you change the HDMI to PC mode on the tv?

I have an LG with similar problems with an Nvidia GFX card. PC mode will fill the whole screen in1 280x720 but the screen is not very clear. I use it in DTV mode and the picture is too big for the screen. I have half the menu bar at the bottom and top and half the start bar on the left and similar on the right.

I had none of these problems with my last pc which was connected to the same tv. HDMI is not all it is meant to be for PC's.
If i had a pc output on my current pc i would use it over HDMI.

sutty

Problem is the D-sub connection on the TV only goes to 1024x786. The High def when it was in 1080i looked a lot better than the D-sub connection as well. But it was the same thing as you. Top, bottem and left and right of the screen, there is about an Icon in distance that can not be seen. This means when ever something is maximised, you can not see the X or the task bar to close it down.

excluding the TV as the problem. What drivers do people use for ATI cards on the highdefs. Is there a good "modified" driver and/or app out there? I'm taking that TV is ok, due to me upgrading drivers and the TV no longer working at 1080i when it did on the old drivers.

mossym

http://www.jvc.co.uk/product.php?id=LT-32DS6BJ&catid=100088&lid=

is this the tv you have?

pH

You don't want to go near 1080i when going from a PC to a flat panel. You want the PC set to exactly the the screen resolution of your panel (if the link above is correct then you want 1366 x 768 ).

If the ATI drivers won't achieve this res then it might we worth looking at powerstrip to see if that can help you.

mossym

that's why i was asking if that was his tv, i have serious doubts he has a 1080 panel at all..

sutty

Yep, thats my Screen, But I did have it working in 1080i mode. Plus the info that cam up from the monitor detection listed as been able to do 1080p res. But if I recall, isn't 1366 x 768 a 1080 res as well?

andy1249

The lads above are correct , your TV only natively supports a 720P resolution with a small bit of upscaling ( 1366 x 768 ) to fit your screen.

Having the PC output at any form of 1080 , ( full 1080 res is 1920 x 1080 ) is a much bigger form of scaling and seems to result in a lot of overshoot for your TV as seen above.

I presume you are using the advanced setup tab in the ATI control panel to set your resolution , if you choose custom resolution under HD in this tab , then you should get a utility that allows you to fill your TV screen at the proper resolution , in your case thats 720P ( same as mine ) .

I am outputting from my HTPC using a DVI to HDMI ( the signals are absolutely identical between DVI and HDMI by the way, just no sound ! ) and am using the latest Drivers from ATI the same as you.

This utility will give you a box that you stretch using the arrow keys on your keyboard until you properly fill the screen. You should end up with a custom resolution that looks something like 1268 by 688 or thereabouts , the reduced figures being an attempt at pixel matching to compensate for the scaling on your TV.
Make sure you save the new res when you are done and it should show up in the HD settings tab as 1268 x 688 at 720p ( res depends on your TV but should be around this !! )
Your new custom res should now be selectable on the normal settings screen for your monitor along with all the standard resolutions , just pull the slider bar over to your new resolution and thats it.

The final picture should be pin sharp.

Give this a shot and good luck !

Idleater

sutty wrote:

But if I recall, isn't 1366 x 768 a 1080 res as well?

It isn't and because the native resolution of the TV is 1366x768, anything else will be scaled to fit into that.

So, giving it a 1920x1080 signal, all it will do is apply some mathematics and squish it down to 1366x768.

Absolutely everything you watch on the TV will be 720p or in other words, 1366x768.

I haven't tried the DVI in on my (LG) TV yet, but it worked fine using the normal VGA when I set the (nVidia) Graphics Card to 1366x768.

L.

P.S. snap andy.

DemonOfTheFall

VGA > DVI for hooking up to a TV.

You can only send standard resses, ie 720p and 1080p over your HDMI connection. In my case anyway.

However with VGA windows detects my tv as 1366x768 instantly.

andy1249

VGA > DVI for hooking up to a TV.

Quite simply not true , DVI/HDMI is pure digital and beats the RGB of the VGA setup easily.
It takes a bit more setting up , but can be done and is well worth it.

Heres a link to the catalyst control centre manual ( X1800 ) ,

https://a248.e.akamai.net/f/674/9206/0/www2.ati.com/manuals/radeonx1800ug.pdf

HDTV setup starts on page 60 .

Have fun

mossym

andy1249 wrote:

Quite simply not true , DVI/HDMI is pure digital and beats the RGB of the VGA setup easily.
It takes a bit more setting up , but can be done and is well worth it.

Heres a link to the catalyst control centre manual ( X1800 ) ,

https://a248.e.akamai.net/f/674/9206/0/www2.ati.com/manuals/radeonx1800ug.pdf

HDTV setup starts on page 60 .

Have fun

quite true, but if i reacll correctly, you can't change the exact resolution over hdmi or dvi, only over vga, so to do 1:1 mapping using power strip you may have to use the vga connection. sendindg over hdmi or dvi could lead to overscan, which is why you'd use vga abd adjust the signal you are sending to compensate

that's if my memory serves me correctly, my tv is 1080i, but only has component inputs, no dvi or hdmi, so i haven't messed too m,uch with the digital interconnects

Idleater

mossym wrote:

quite true, but if i reacll correctly, you can't change the exact resolution over hdmi or dvi, only over vga,...
sendindg over hdmi or dvi could lead to overscan, which is why you'd use vga abd adjust the signal you are sending to compensate

I agree. With my tv, using DVI/HDMI from a dvdplayer is different to from a computer.

I think one is assumed to be 720p (or 1080i to be converted to 720p) and the other is assumed to be from a computer in which it sets the resolution to be 1366x768. These are switched by selecting HD/PC on the TV menu.

The manual says that before doing this, I should have the computer's graphics card set to 1366x768 and then connect the dvi to the TV.

Using vga to dvi on the other hand, I can change between all the "normal" resolutions, 640x480 up to 1366x768 on the computer.

L.

mathias

OK , heres exactly how I set mine up , including a photo of my TV showing the screen the Catalyst driver throws up to let me adjust the picture size , my tv has no VGA port , and I am using the second HDMI input , note I have no option to switch this input between TV / PC , it just works ,


First I go into the catalyst control centre ,
See the pic CatCC

See the instructions half way down ? I pick a standard HD res and click on apply , then add , and a resize screen comes up , this is it ,
See the pic adjust ,

This is a photo of the TV , excuse the bad res , Im trying to keep the size down for upload , but you see the arrows and the res figure boxes , you click on the arrows till you can see the edge of the box on your TV screen.

When your done you save it and your res comes up in the standard settings box like so ,

see settings pic below ,

And thats it , picture resized for your LCD TV over ad straight DVI/HDMI cable.

All catalyst drivers have the same control centre right ?

Balfa

andy1249 wrote:

DVI/HDMI is pure digital and beats the RGB of the VGA setup easily

This is not necessarily the case. It's true that the signal will deteriorate over a VGA cable, but the signal also deteriorates in the Digital to Analogue Converter (DAC). If the video card's DAC is higher quality than the TV's own DAC, then using HDMI (which bypasses the video card's DAC and uses the TV's, instead) can actually result in a lesser quality picture, especially if your VGA cable is very good quality.

This is going a little off topic, but I thought you might find the information useful, or at least interesting

edit: You just have to try both and see which looks best. For most TVs, HDMI will probably win.

mossym

am..no, the vga will be converted back to digital as soon as it hits the tv...so if you feed a tv a digital signal, it's converted once. If you go vga, it goes digital to analog to digital to analog...so it's going to through the lesser converters as well

pH

Agreed

Even though the process of lighting a pixel is technically an analog one, because flat screens don't scan pixel by pixel like a CRT, any analog signal sent to a flat panel is digitised and buffered.

Balfa

pH wrote:

any analog signal sent to a flat panel is digitised and buffered.

Aharr, right you are, of course. I read the above in something specific to CRT-based HDTVs, and then promptly forgot it was specific to CRTs