Computer sounds like a police siren

Now the computer boots and gets to the desktop--no siren, but reboots over and over--this could be an OS problem???



I have an older computer that was working just fine. I usually leave it turned on all the time. I left town for one week and my wife shut it down the day I left. Upon my return, I tried to start the computer and a siren went off and it would not boot. After some initial internet searches, it appeared to be an overheating issue. Sure enough the power supply fan was frozen. I replaced the power supply and the same thing. I checked everything inside and finally got it to start up in safe mode. I ran an error check using windows XP and no errrors were found. When I try to boot normally, it starts up, gets all the way to the desktop, the siren goes off and it shuts down. If anyone has any idea or can give me some advice, I would be greatly appreciative.--David

Edited by Waterhead, 07 February 2009 - 10:39 PM.

Overheat protection may be kicking in. Is the heatsink on properly and the fan turning?
If you can in to BIOS, Check your temperatures and the maximum temperature that the alarm monitor triggers at in the motherboard's utilities. Sometimes you can change temp and fan speed setting, you could possibly
increase the warning limits.

In my bios, I can go to Hardware Monitor. CPU Smart Fan temp shows 50 c/122 f.

PC Health Status tells me that the actual temp is 34 c/96 f

If this means what I think it does (correct me if I'm wrong) when the temp of my sytem reaches 50/122 I will be notified that it's getting to hot.

If I remember correctly, change temp and fan speed is done under Hardware Monitor.
It may be a simple matter of the temp being at a level which makes the siren sound and changing could clear up the issue.

And it may not, but might be worth a try.

If you need help with this, post back with your bios (Phoenix Award, etc)

Also had another thought: While you have the case open, look to see how much dust in inside. You might need to clean out the innards. Dust can clog up and affect fans and temps.

http://www.ehow.com/how_3664_clean-computers-insides.html

regarding number 4-I always unplug the power source to the computer.

Edited by Queen-Evie, 08 February 2009 - 04:14 AM.

I'd also check to see if your video card has a fan - and if it's working also.
Beyond that, take a look inside the case to see if all fans are working when you turn it on.
BE CAREFUL not to stick your hands inside the case or touch anything inside the case when the power is on!!!

I put out a call to those who know more about this issue than I do.
Usasma responded, as did Platypus.

Platypus stated:

'The "police siren" sound is indeed typical of a CPU overheat warning, but another possibility is a false warning caused by bad capacitors - this was a well known cause for Dell "Thermal Event" warnings. It could also cause his present rebooting cycle. '

I was swapping out some parts yesterday and all of a sudden got this Police siren when I tried to boot.
I Pushed the main power connector to the MOBO in further and it stopped immediately.

Worth checking