optimizing display settings for tv

[severdhed]

I have a 27 inch tv in my cab connected via component video,  the picture looks fine,  however I get small black bars on either side of the picture, probably about 3/4 of an inch thick. It also seems as if the top and bottom are cit off slightly,  not just in mame,  but at the xp desktop as well.  Any ideas? I looked through the tv menu,  but couldn't find any adjustments.  The playstation looks just finegoing through the same component input.

[RayB]

Those kinds of adjustments are usually hidden in what's called a "service menu". Just Google your specific make and model # for this menu. It usually requires a series of button pushes on the tv and/or remote control to bring up the secret menu.

[Ginsu Victim]

Your video card software should let you adjust it.

[MonMotha]

TVs actually draw video beyond the edge of the area you can see in order to ensure that the picture fills the entire screen and to hide minor (or sometimes major) imperfections in the edge geometry.  This is called "overscan" and the amount is typically 10-20% of the picture being off the screen (so quite a lot).

What your PC is doing is actually resizing the video to be smaller and placing it inside a black box.  Since PC graphics are always assumed to have no overscan (the image is adjusted to go right up to the edge of the monitor and no further), the edges of your screen would be cut off if this were not done when outputting to a TV.  This is colloquially referred to as "underscan" by way of being the opposite of overscan.  Unfortunately, since the range of overscan on TVs varies so widely, the defaults for the underscan on PCs have to be pretty conservative resulting in visible black bars around the picture.

Most PC graphics drivers have an option to adjust the amount of underscan/overscan.  You can often just grab a slider and drag it until the image fills your entire TV screen without cutting anything off.  Easy peasy.

The best picture is attained by setting the control to "full overscan" as this results in the least amount of scaling (down) of the PC graphics.  Unfortunately, this will chop off the edges of your display.  It is sometimes possible to adjust the TV's geometry to remove the overscan in service mode, but it's often a pain in the butt, and if you mess up, you can render your TV pretty well broken.

[releasedtruth]

I use a 25" TV via component as well and to reduce overscan I used powerstrip to set my resolution to 640x432 which produced a perfect fit when using MAME and various front ends. Might want to give powerstrip a try.

[severdhed]

i'll have to look at it more closely this evening.  it is an ATI card, i dont remember which model off the top of my head, but i do have the catalyst control center installed, it may have the options to try it out.. the problem i have with it is when i open the program, it is too large, i cant seem to get to the apply and OK buttons because they are off the bottom of the screen and i can't drag it up any higher.  i'll have to look at powerstrip.

[newmanfamilyvlogs]

Does the card support two monitors? Perhaps you could have a 'service' monitor you hook up to the second output to drag the window onto, make adjustments to the primary display (the tv) then disconnect the second monitor once you have it dialed in.

[severdhed]

yeah, the card does support multiple monitors, i actually havea  17" lcd sitting on the floor next to teh cabinet, i guess i could hoook that up

[Ginsu Victim]

I have the same problem with Catalyst Control Center. I have to use a second monitor for any adjustments.

Hmmm, I wonder if I extend desktop and put the monitor underneath instead of to the side, that way I could make the adjustments while in 640x480...

[severdhed]

well, i got this partially resolved.  i hooked up an lcd monitor as a second display, set it to 640x480 as well, and positioned it below the first monitor.  that way the OK and Apply buttons were visible on the second monitor.  i then changed the resolution of the tv to 640x432, and played with the overscan until it filled the screen.  not only does it fill the screen, but it looks so much clearer on the windows desktop. 

i have to make a new mala layout because the one i am using is fixed at 640x480. 

however when i launch games in mame, they still have black bars on the sides.  i can eliminate it by forcing a stretch, which doesnt squash the horizontal games too much, but it makes the vertical games look horrible.  if only there was a way to stretch only the horizontal games, without manually setting it for each rom.  i guess it isn't that big of a deal, but it just bothers me a little.  at least the windows desktop and front end fill the screen now.

thanks for your help and suggestions.

[releasedtruth]

Interesting, I don't have the stretch on vertical games (GameEx applies bezel) and I'm running 640x432 on an ATI card with Powerstrip's help. If it helps any, I'm using MAMEUIFX32 and GameEx as mentioned. As long as  you have a software bezel applied, should work fine.