Go Back   nV News Forums > Linux Support Forums > NVIDIA Linux

Newegg Daily Deals

Thread Tools
Old 07-08-05, 11:00 AM   #1
Registered User
Join Date: Jul 2005
Posts: 14
Unhappy hdtv overscan does not work under v7667

I have a geforce 6600GT (MSI, PCI-e) running under 2.6.12, and find that using

Option "ConnectedMonitor" "TV"
Option "TVStandard" "HD1080i"
Option "TVOverScan" "0.0"
Modeline "1920x1080@65i" 85.12 1920 1952 2272 2304 1080 1104 1110 1135 interlace

I get a nice image which is unfortunately too large for my 16:9 TV.

Changing the TVOverScan value makes no difference, and unfortunately I can't construct a custom Modeline, as the NVidia driver enforces some idea of standard output sizes.

I would like to be able to adjust the overscan under 1080i, as I can under lower resolution tvstandards and under windows. Alternatively, I would like to be able to specify a modeline which conforms to what my TV displays.

I am sending my nvidia-bug-report off now, but it seems to me now that this driver version is broken by design.
colinmcc is offline   Reply With Quote
Old 07-08-05, 11:07 AM   #2
Join Date: Jul 2002
Location: Netherlands, Europe
Posts: 2,105
Default Re: hdtv overscan does not work under v7667

Overscan doesn't work fine at all at the moment, which is a known problem. Further doesn't your HDTV have a DVI-input if so really use that one as when you use DVI you don't need overscan at all and the image will be a LOT better than using s-video. Note that it is quite insane technically to use S-VIDEO for 1920x1080 as it was never made for such high resolutions and frequencies. (signals with frequencies of lets say 150MHz need to travel accross the cable for which it isn't made; the image quality will be very poor)
Thunderbird is offline   Reply With Quote
Old 07-09-05, 03:48 AM   #3
Registered User
Join Date: Jul 2005
Posts: 14
Default Re: hdtv overscan does not work under v7667

I was operating under the (mis?)understanding that component video (not s-video) was capable of supporting HDTV, and that is what I am using, as that is what the card and TV provide.

I was unaware that overscan compensation doesn't work with the linux driver. I begin to see the downside of a closed source video driver.
colinmcc is offline   Reply With Quote
Old 07-11-05, 01:31 PM   #4
Registered User
Join Date: Sep 2004
Posts: 50
Default Re: hdtv overscan does not work under v7667

Thunderbird, although the component video dongle attaches to the s-video plug, it is using distinct signaling that has nothing to do with s-video. So the signal is full-resolution 1080i. As far as I know, this is supported on most of the 6xxx or newer series of cards.

colinmcc, yes, overscan is a hard problem to solve for lots of reasons. For one, your TV was designed to be overscanned. Any 1080i signal it receives will be cut off at the edges. That was an intentional decision by the manufacturer, and is present in almost all tube displays, although rarely present in LCDs and plasma displays.

Overscan compensation with composite and s-video output is easy to fix because the framebuffer's pixels and the display's pixels are not mapped one-to-one, so you can just "squish" the image a little more. With 1080i using component output, that doesn't make sense, because the pixels have a one-to-one correspondance. Squishing them would produce an ugly image.

What you really want to do is just tell X to use the same 1080i signaling resolution to your television, but only use, say, the middle 1800x1000 of the image for actually displaying data. This can be achieved without involving the NVIDIA driver. There are two ways that I can think of:

1. Use a modeline like this:

Modeline "1920x1080@65i" 85.12 1800 1952 2272 2304 1000 1104 1110 1135 interlace

Note that it is identical to your mode above, except the utilized screen area is 1800x1000 instead of 1920x1080. Your TV sees the same signaling data though. However, I can't guarantee that the NVIDIA driver will accept this mode. It ought to though. I know that the horizontal resolution must be a multiple of 8, but other than that, you should be able to alter the resolution freely.

2. Change Xorg to only utilize some fraction of your screen for displaying window data. I know of no built-in option to do this. However, it could be achieved by only modifying Xorg code, and not touching the NVIDIA driver, and in fact, this would be the "most correct" way of doing overscan compensation in software.

Let me know if you have any success, or if any of my analysis is faulty.
davemoore is offline   Reply With Quote
Old 12-22-05, 11:07 AM   #5
Registered User
Join Date: Dec 2005
Posts: 7
Default Re: hdtv overscan does not work under v7667

Has anyone managed to solve the overscan+1080i+component+linux issue? I have exactly the same problem.
korpenkraxar is offline   Reply With Quote

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Removal of overscan options in 302.07... hikaricore NVIDIA Linux 12 01-05-13 04:30 PM
HDMI overscan fix for multiple resolutions + Zod Engine Problem. cheechr1 NVIDIA Linux 0 06-11-12 02:27 PM
Blu-ray 3D Movie Playback With PC on a 3D HDTV Using HDMI 1.4 News Archived News Items 0 05-16-12 03:30 AM
295.40 Does not Work Had to downgrade to 295.33 Archmbc NVIDIA Linux 4 05-03-12 02:38 PM
HDTV support - computer to HDTV set porksoda NVIDIA GeForce 7, 8, And 9 Series 10 10-27-05 06:30 PM

All times are GMT -5. The time now is 01:13 AM.

Powered by vBulletin® Version 3.7.1
Copyright ©2000 - 2015, Jelsoft Enterprises Ltd.
Copyright 1998 - 2014, nV News.