I plugged in my xbox 360 to my dell flat pannel monitor using hdmi to dvi cable and it reads cannot display video mode

HDMI is digital
VGA (the 15 pin connector) is analog.
If your connector has the digital to analog interface it should work, but likely it does not have that chip and thus will not work.

Your description of the problem tells me it may never work as you have it connected. Possibly it might be that the monitor is required to be powered on before the laptop is booted, but that only works in some cases.

I have also seen some work if a 2-step connector is used.
VGA to DVI connector, followed by DVI to HDMI connector.
DVI was the step toward digital that came before the HDMI standard was implemented and was only partially digital. DVI and VGA do not carry control signals nor audio. HDMI carries both those as well as the video.

YMMV but I think it would be cheaper and more efficient to actually purchase a monitor with a digital input (HDMI or DVI).
Without the digital/analog converter interface a digital output device (your laptop with HDMI out) can never operate an analog device (your Dell monitor with VGA input).

As far as I know, the DVI cable can't send sound, so if you could use a only-HDMI cable or SCART cable, that should give you both picture and sound.

You need a HDMI to DI cable not HDMI to d-sub cable. The sellers that are selling that cable do not tell you that it will only work with special video cards that output analog to the HDMI connector. HDMI is digital and so is DVI so they will adapt to each other. Keep in mind that this is for video only, sound will not work on the monitor because the DVI port does not support sound. You will need to add a set of speakers to the Xbox

I am not an xbox person, but as far as hooking it up, it should work as long as the other device is NOT powered up. That being said you will still have to provide audio from the xbox another way as dvi only carries a video signal, unlike the hdmi which carries both audio and video.

How do you connect the XBOX audio line out to the monitor audio input? If the xbox HDMI output is set to send the digital audio through the HDMI cable, you will not get the sound since you are using HDMI to DVI because the DVI is not made to accept the digital audio. You will need to to use the XBOX analog audio output instead feeding the audio cable with mini stereo phone plugs, please read XBOX user manual.

Basic LCD monitor and TV troubleshooting guide:
http://www.fixya.com/support/r6150077-basic_lcd_monitors_troubleshooting
http://www.fixya.com/support/r5093881-lcd_flat_panel_tv_troubleshooting_guide
http://www.fixya.com/support/r7406380-tv_training_manuals
Failed TV and Monitors: http://s807.photobucket.com/albums/yy352/budm/

Learn about bad caps: http://en.wikipedia.org/wiki/Capacitor_plague

Capacitors kit: http://lcdalternatives.auctivacommerce.com/ he can make you a set of caps for you.

Or www.digikey.com just make sure to use caps with low ESR, 105c, high ripple current, long life rating such as PANASONIC FM or FC series.
Please leave rating if it helps.

Your Dell Monitor does not have a video output. The DVI/HDMI cable needs to run from the DVI-Out of you computer tower directly to the TVs HDMI input, ideally one with a red/white analog audio input next to it, because that cable only provides a video signal. If you don't have a DVI out on your computer, perhaps your TV has a VGA input. If your computer/video card only has one monitor connector, then you can only connect the Monitor OR the TV.

HI,
Your LG LCD monitor has a white DVI connector for connecting the signal cable.

You would reqire either an HDMI to DVI(male connector cable for the xbox) so that you can hook the hdmi cable to the xbox and other end to your monitor.
The cable would look something like this
http://hardware.teamxbox.com/reviews/xbox-360/40/Xbox-360-VGA-HD-AV-Cable/p1/

Thanks
proton

ok i think you need to reset the video settings here is a step by step procedure which you can follow

To reset the display settings of the Xbox 360 console to the default settings, follow these steps:

1. Remove any discs from the disc tray.
2. Turn off the console.
3. Turn on the console.
   
   Note If you are using an Xbox 360 Wireless Controller, turn on the console by using the Xbox Guide button on the controller. Wait for the guide light to indicate that the controller has linked to the console.
   
   Note Make sure that you use the player 1 controller when you do this. The player 1 controller is indicated by the upper-left quadrant light on the console.
4. As the console starts, press and hold the Y button as you pull the right trigger.
   
   Note This action causes the Xbox Dashboard to reset the display settings to the default settings. The console then automatically restarts.

You cant have HDMI and the xomponent cables pluged in at the same time.
to get audio to your monitor you will need an xbox 360 audio adapter. You can find that here. http://www.xbox.com/en-us/hardware/x/xbox360hdmiavcable/default.htm

That comes with the HDMI and audio adapter.
You can probabaly find it seperate somewhere else.

I hope this helps.

As long as the phono socket is red or white. That represents Audio