My computer has no audio device all the sudden?

you need to reinstall the sound card driver you can find it free at the maker of your computers website ie www.compaq.com

Are you using on-board sound? Assuming sound you are talking about music, etc. Not specific CD player or DVD.

First of all, double click on the speaker Icon in tray and if it is shrunk, expand out all the controls. Somewhere there you should see the sound levers for all. Push all with mouse to top volume and make sure nothing is muted.

If still does not work, did you install a keyboard that has sound control. Example I have Microsoft wireless and control much from there also, depending upon my mood.

If still not working then we can continue.

Enter into Control panel, then system, and find device Manager and double click it. In there you should see someting as to sound, video, game controllers.

Click on it and expand it out. Then you should see what you have installed at this moment. Double click on any one line that should say something bout PCI audio (if you have sound card installed) THen on tabs of the window, you can see in General, if it says "This device is working properly". If not you can check on other tabs. It might have lost a driver.

If external board, your onboard sound must be off. If on-board, it might have gotten reset but not normal.

Before you go into redoing it, and have onboard sound, power down fully, then do a reboot into the ROMBIOS and check settings that it is enabled. If onboard, does not work, consider uninstalling all sound drivers, and all audio software. Also did you previously install camera, mic, or what ever:

If you use on board sound, they usually go first. which is good as 20 dollar sound card is cheaper than new mother board.

But uninstall all, and redo it. If it still does not work, it could have zapped. I have always had pains with sound on board, and some sound cards. They blow faster as we tend to drive them hard.

I had a new computer, AMD dual, and so much trouble with onboard, I bought a 15 dollar boards, and works perfectly through external amp.

in line with possibility the sound card is fried or the gadget became unplugged via a tugging on the cable. First examine the cable. If each and every thing is hooked in suitable, look into getting a clean soundcard. A no longer-too-fancy yet working soundcard in basic terms expenses approximately 25 money.