I have a Compaq presario R3000. I suddenly started facing a strange problem. When I power on the laptop, I see the 'battery charging on AC power' icon. Once the battery charges 100%, the battery icon comes on and it is no more running on AC power. Once the battery discharges, the laptop hibernates. If I re-power on the laptop, the same cyle repeats. I've tried disabling/enabling ACPI settings but not successful in fixing it. Any suggestions are most welcome.