Dead battery or dead motherboard?

JDR · 02-10-2009, 10:22 AM

Hi everyone:

Im having problems with my alienware area 51 m9750 that ts 14 moths old

Some months ago i noticed that the battery only lasted 25 minutes, and i just thought it was because i hadnt fully charged it, but then when the charging indicator showed a complete charge the same happened again but not the time was reduced to 15 minutes. I started to look around the net and found that not only the battery could be the problem but a circuit in the mother board as well. then i remembered two important things:

1) Since i got the computer i hadnt given appropriate maintainance to the battery i used every day plugged to the power and never gave it the chance to run on battery and let it discharged (i know huge mistake by me) and as far as i know this must be done to keep the battery healthy.

2) The thing that worries me now is that one day (dont remember whether it was before i noticed the battery didnt work or after that) i was working on my lap when suddenly my place suffered from a low voltage supply, everything went off except my lap, as the work i was doing was very important (and i was working listeting to music with headphone on) i didnt notice that the power brick was doing a strange noise, like buzzing, i think it did that for about 5 minutes and i unplugged. Currently it works fine but i was wondering if this couldve damaged the circuit in the motherboard.

When the lap turns off due to lack of battery i try to check voltage with my voltmeter and the batetry does provide the 15 volts, the lap just wont start.

Finally, when the computer is running on battery the battery indicator next to the clock in the toolbar tells that the battery will last for 4 hours (obviously this is impossible, and the computer turs off after 5 minutes) but i dont know if it has to do with the motherboard not regulating correcly.

Any help will be much apprecated.

**TriggerFinger** · 02-10-2009, 10:48 AM

Does the laptop switch ON or boot up with AC only? If so, have you tried another battery (good and working)? If you have ruled out the battery then it could be the motherboard or the power circuit board (if there is one).

JDR · 02-10-2009, 11:00 AM

Hi there, thanks a lot.

Yes the lap starts and works fine with AC only with the battery in and out. A few minutes ago the battery was supposed to be fully charged i turned on the lap logged in but after three minutes the lap turnef off, i checked the battery voltage and it delivered the 15 volts, left the battery alone (not connected to anything) checked voltage again and its at zero, this makes me go for the battery having issues more than the motherboard, but not sure, as for the indicator saying the battery will last 4 hours what do you guys think that means?

Unfortunately i cant plugh another battery since i am not in the us and you know this brand is practically unknown outside this country.

Any further help will be thanked

02-10-2009, 10:22 AM	#1 (permalink)
JDR Registered User Join Date: Feb 2009 Posts: 2 OS: Windows Vista Home Premium SP1	Dead battery or dead motherboard? Hi everyone: Im having problems with my alienware area 51 m9750 that ts 14 moths old Some months ago i noticed that the battery only lasted 25 minutes, and i just thought it was because i hadnt fully charged it, but then when the charging indicator showed a complete charge the same happened again but not the time was reduced to 15 minutes. I started to look around the net and found that not only the battery could be the problem but a circuit in the mother board as well. then i remembered two important things: 1) Since i got the computer i hadnt given appropriate maintainance to the battery i used every day plugged to the power and never gave it the chance to run on battery and let it discharged (i know huge mistake by me) and as far as i know this must be done to keep the battery healthy. 2) The thing that worries me now is that one day (dont remember whether it was before i noticed the battery didnt work or after that) i was working on my lap when suddenly my place suffered from a low voltage supply, everything went off except my lap, as the work i was doing was very important (and i was working listeting to music with headphone on) i didnt notice that the power brick was doing a strange noise, like buzzing, i think it did that for about 5 minutes and i unplugged. Currently it works fine but i was wondering if this couldve damaged the circuit in the motherboard. When the lap turns off due to lack of battery i try to check voltage with my voltmeter and the batetry does provide the 15 volts, the lap just wont start. Finally, when the computer is running on battery the battery indicator next to the clock in the toolbar tells that the battery will last for 4 hours (obviously this is impossible, and the computer turs off after 5 minutes) but i dont know if it has to do with the motherboard not regulating correcly. Any help will be much apprecated.

02-10-2009, 10:48 AM	#2 (permalink)
TriggerFinger Moderator Hardware Team Join Date: Jan 2008 Location: USA Posts: 11,847 OS: Vista SP1, XP SP3, PCLinuxOS2007	Re: Dead battery or dead motherboard? Does the laptop switch ON or boot up with AC only? If so, have you tried another battery (good and working)? If you have ruled out the battery then it could be the motherboard or the power circuit board (if there is one). __________________ DBAN - Memtest86+ - BartPE - Linux LiveCD - ImgBurn - HDD Diags - Disk Copy HOW TO BURN AN ISO FILE

02-10-2009, 11:00 AM	#3 (permalink)
JDR Registered User Join Date: Feb 2009 Posts: 2 OS: Windows Vista Home Premium SP1	Re: Dead battery or dead motherboard? Hi there, thanks a lot. Yes the lap starts and works fine with AC only with the battery in and out. A few minutes ago the battery was supposed to be fully charged i turned on the lap logged in but after three minutes the lap turnef off, i checked the battery voltage and it delivered the 15 volts, left the battery alone (not connected to anything) checked voltage again and its at zero, this makes me go for the battery having issues more than the motherboard, but not sure, as for the indicator saying the battery will last 4 hours what do you guys think that means? Unfortunately i cant plugh another battery since i am not in the us and you know this brand is practically unknown outside this country. Any further help will be thanked