Dell D620 - Battery Is Good but Computer only works on AC Power Adapter

Hi All,

I have a Dell D620. I bought a brand new battery for it off eBay. However, my D620 does not power on with the battery installed. The machine turns on only if using the AC power adapter or when attached to the port replicator. If it is plugged into the adapter, the moment I unplug it, the machine goes off immediately - total loss of power.

The machine will recognise the battery, charge it to full capacity, but will not power on unless the AC adapter is plugged in. The bios says the battery is good, and shows the charge. Nevertheless, thinking it may be a dud battery, I went to a second hand computer store and tested it in another machine (D630), to make sure it works. It turned on the Dell D630 no problems--even showed 4hrs of charge remaining in the WinXP battery meter.

Can anyone point me in the right direction. Is this a Mainboard issue? or is there some other connection inside the computer that may be loose. I pulled the computer appart a couple of times in the past to clear the dust from the the air intake behind the cooling fan as the CPU had been overheating. Once the dust was cleared out the computer ran fine. However, I had to do this one more time just now, before I got the new battery. My old battery gave me about a minute of charge time before turning off. Now it does the same thing as the new battery. Neither one turns on the computer. Totally dead. Perhaps I've done something in the process of cleaning out the dust to cause the battery to fail powering up the computer. Not sure though.

Any suggestions appreciated.

Thanks.

Dell D620, 4GB Ram, Centrino Duo T2400 @1.8Ghz, Bluetooth, DVD R/W, 60GB HDD, WinXP Pro SP3.