I've been having a strange issue the past few days. After my laptop is on for approximately 10-15 minutes, the ATK program starts switching back and forth from Battery Mode to AC Mode constantly. When I checked the AC connection I noticed the metal tip that goes into the DC jack was very hot. By hot I mean I couldn't hold it for more than a second without burning my fingers. I then checked the battery and noticed it also was very hot where I couldn't even hold it in my hands. At first I thought it was my AC adapter since it is kind of frayed at certain points, so I purchased a new one on Amazon with the same voltage/amp specs. The issue was still occurring, so I removed the battery and to my amazement the ATK program still says its switching from Battery Mode to AC mode which is impossible since I removed the battery and the system never shut off during this time.
I updated the BIOS on the machine to the latest revision for my model which is 205. I then did a fresh installation of Windows 7, but neither worked. I even drained the battery completely and tried to recharge it. The battery does recharge so it's definitely getting power from the AC adapter, but the overheating still occurs. I tried blowing dust out of the fans with an air compressor, but hardly any came out. I also checked system temperatures using HWMonitor which report the CPU at 50 celsius idle. The laptop usually runs at 35-40 celsius idle, but I'm thinking the battery overheating might have been raising the temperature somehow, or the sensors on the motherboard are faulty.
I had the motherboard replaced on my laptop back in August of 2011, and haven't had any issues until this point. I think it's the motherboard that's the issue, but only because I can't think of what else it could be. I currently have a ticket open with Asustek Support, but wanted to post on these forums to see if anyone has experienced these issues or has a different perspective. Thank you for your time.