does the computer have onboard graphics card or an installed one,no signal errors are because the graphics arent being detected any longer,if the card is bad its best to replace it,otherwise enter bios screen and check to make sure the bios didnt reset to factory defaults,if the graphics option is turnd off,turn it back on by usually useing the + or - button on your keyboard.

A No Signal message comes from the monitor, not from the computer. It means the computer isn't working. If nothing has been touched inside the system, it sounds very much like something was electrically damaged when the shut down/ power up occurred.

Probably best to take it to a repair shop to get it checked out. But first, check all power boards plugs and power leads to be sure that the problem isn't actually between the wall outlet and the computer. If there are any noises from the PC, like fans spinning etc, then it's highly likely a fault somewhere causing this.

The only thing you can do yourself really, if you are handyman minded, is to open up the case (make sure it's disconnected from power) and carefully check that all plugs components and cards are firmly and securely plugged in. Sometimes a display card working loose in its slot can cause this, or a monitor lead not plugged in securely etc etc.....

I just got this problem on an old pc that has been working fine until this AM. I turned it on and it hung and hung during the light blue windows xp screen, the one just before the desktop screen.
I pushed reset on the pc tower and this time it hung on reset, no POST, and kept making a beeping noise l like the reset button got stuck. The monitor, after showing it's splash screen for Acer, gave me the "no signal message" on screen and went dormant. I unplugged the pc tower, waited and replugged, no no avail. Another thing, the fans run on power on fine, but oddly the temp monitor says 33º C, which is hot for a machine that was just off all night. It should be around 20º C or room temperature.

I opened the tower, dusted everything off with air brush and restarted. The beeping is gone but the no signal screen comes on still. This PC is 5 years old, always worked until today. Some things have been upgraded memory, graphics card, 2nd HD, network cards, voice modems, over the years but but nothing newer than 3yrs ago.

From reading here, I have learned this error means the pc is not functioning. The WINXP OS is on the older HD. Could it be failing?

Would switching to a new hard drive be worth a try?

Is there an on-board graphics ?
If so try connecting your monitor to that.
You may have to enable it in the BIOS setup.
Remove the PCI graphics card beforehand.
If the pc works fine when the monitor is connected to the on-board graphics -then your PCI graphics card is faulty. and needs replacing.

There is no on board graphics card. Thanks.

I just checked the gygabyte motherboard manual on error messages. According to their list the beeping I heard corresponds to a faulty power supply.
I will be trying a new psu.

Success!
I installed a new power supply, an 420w xilence. Then before starting up, I disconnected the monitor and network to clear any residual error messages from the memory.
Booted with one good beep (or burp .-)), it asked if I wanted safe mode or normal, let it go normal. Then I shut down, connected the monitor and network and started up again. All systems go!
I will be looking for a power tension monitor and safeguard, since the source of the problem was apparently a power surge than opverrid and broke my power outlet base anti-power surger.

First u plug off the connections from the main supply.open your cpu and clean it with smooth brush and give the connections rightly and then switch on.
===========================================================arnold
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