Bios Battery

A full blown motherboard schematic is available here: http://www.4shared.com/get/3jbAtfnn/COMPAL_LA-4201P_-_REV_10.html

Image of motherboard here: http://www.ascendtech.us/itemdesc.asp?ic=MBLACELA4201PSB&eq=&Tp=

Looks like the battery is soldered in.  I believe it is the small round button cell with the blue edge.

Much bigger image here: http://i03.c.aliimg.com/img/ibank/2010/031/262/238262130_2014839378.jpg

• Read through the owner's manual for your particular Acer Aspire laptop to determine what kind of CMOS battery you need. Purchase the battery through Acer or a local or online computer parts dealer. Turn the laptop off and unplug it. Also unplug any external hard drives, cameras, or other external devices. Turn the laptop over (bottom facing up), then touch something metal to remove static charge.

• Remove the Phillips screws that secure the motherboard cover (refer to your owner's manual if necessary), then release the cover from the clips on the bottom of the plastic casing. Lay the cover aside then locate the CMOS battery cable on the right side of the motherboard. Unplug the cable then remove the battery.

• Plug the new CMOS battery cable into the motherboard. Slide the battery partially under the laptop casing to hold it in place, then align the cover with the slots on the bottom of the laptop housing. Replace the screws then turn the laptop back over.

• Plug the laptop in and turn it on. Enter your BIOS (usually by pressing "F1," "F2," F10" or the "Delete" key) before the operating system loads. Follow the BIOS prompts or refer to your Acer Aspire owner's manual to reset your time, date and desired system settings.

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  • Anytime the CMOS battery is unplugged for more than a few seconds your BIOS will be reset to the default manufacturer settings. If you make any changes to the BIOS that cause problems with your Acer Aspire, unplug the CMOS battery for 3 to 5 seconds to correct the problem.