Does a missing pin in a 15 pin d-sub vga cable affect the resolution options connecting a laptop to a tv?
I want to connect my laptop to my lcd tv with a 15 pin d-sub vga cable. both laptop and tv have vga sockets and when i connect a short vga cable that i use for an external monitor, i can set the tv as an external monitor with a widescreen resolution. however, having bought a new belkin gold series cable to dedicate to the laptop/tv connection, i can only choose 4:3 aspect ratio resolutions for the tv.the short/original cable has all 15 pins, whilst the new cable only has 14, with pin no.9 (i think) missing. this seems to be standard on loads of replacement vga cables out there.is it the lack of the no.9 pin that is causing the problem, or is there some other reason? is there a 5m cable out there that anyone can recommend that will allow me to run widescreen resolutions on a second monitor from my laptop (dell d420) running windows xp pro?thanks!
Answer
Rodger appears to be using an old pin specification.
pin 9 is a 5v supply from the system to the monitor. the reason for this is to provide power for the ddc circuitry in the monitor so that the plug-n-plat will still work if the monitor is off.
it is possible that your tv is not
providing it is
own power to the ddc circuitry and relies on the power from the system coming up pin 9. a
odd design, but possible.
the other option is that the actual ddc signals that pass the plug-n-play information from the tv/monitor to the system are losing quality over the longer cable length. i would suspect that this is more likely.
you should be able to go click on the advanced button of the display properties settings tab, then select the adapter tab. there is a check box of hide modes not supported by the monitor (or something like that) clear that and you should be able to select any resolution that the system is capable of.
make sure you do not go beyond the resolution/frequency range the monitor supports because you will
get a blank screen, that can be hard to recover from if it is your primary screen.