Have no sound on a dell d800. "No audio device

Quote "Some monitors come with built-in speakers. If your monitor has built-in speakers, use this document to troubleshoot audio difficulties before troubleshooting the devices connected to the monitor." from http://support.hp.com/,
this is just an example.
So I would go to the manufacturer's website/support.

check in your control panel and go to systems.
Then go to hardware and under that go to Device Manager
In there see if there are any exclamation marks in your sound hardware,
conflicts and such.
If there are none then go to Sound Controls in Audio Devices and make sure the audio isn't muted in the windows program
Use this to do an audio test of your speakers.
If that isn't working but it should be check your wires to see if there is a break or if it is plugged into the the green colored jack for external speakers.

The Dell Support web site only offers audio drivers for Windows XP or earlier versions of Windows.
If you are using Windows Vista or 7 then you will probably have to rely on the default audio driver that these versions of Windows will load automatically when installed as Dell do not offer an official device driver for these versions.
The alternative approach if the built in sound device is not recognised and you cannot find a suitable device driver would be to buy either an internal sound card or a USB sound card - the latter just plugs into the USB port, provides the normal audio sockets and can be used to connect your speakers, headphones, microphone etc.

Go to the Dell web site and down load new drivers for your speakers. then they will work.

THIS WILL HAPPEN IF:
-if your speakers are plugged in the wrong hole
-if the power adapter from the wall to the speaker fails
-if the speakers are muted in windows sounds properties (double click speaker icon by clock on desktop to check-making sure the MUTE box is NOT checked)
-if the sound card drivers are corrupt or not installed
(right click "right click "my computer" left click "properties"- click the "hardware" tab at the top- click on the "device manager" button
scroll down to where it says "sound and audio" with a + next to it. if there is a yellow ! or ? it means that your software drivers for the sound are corupt or missing and will need to be reinstalled using the install disk or downloaded drivers from the dell website which are free.
Regards.

This sounds like a defective audio port. In normal operation, plugging in a headphone plug breaks the connection to the speakers. On your laptop, when you pull out the plug it makes a connection, but only briefly. Unfortunately the audio port is built into the system board. I don't think you will find a software fix for this problem. Your best bet is to get a USB sound device for external speakers.

go to the speaker icon at the bottom right of screen and left- click and then click mixer ,make sure the speaker icon is turned right up and the mute is not "checked" uncheck it. if this fails you may have to reinstall your audio drivers

Select your model on website below to download drivers:


Dell Drivers and Downloads

To make it easy for you this is the default audio driver for Dimension 2400 systems. Click on this link ---> http://support.dell.com/support/topics/global.aspx/support/downloads/en/downloads_splash?c=us&l=en&s=gen&~mode=popup&file=122481
this would install your integrated audio driver for your system.
Let me know if this resolved this issue.

Go to Dell's support site and download any updated sound drivers. Then uninstall the sound drivers from the device manager, the reboot. It will find the hardware and reinstall the drivers. If this doesn't work, then it's an issue with the speakers. Check the connections to see if they worked loose, if not they may need replacing.