The battery won't charge on my SP3. We lost the original charger, and have been using the dock we ordered with it, the machine won't charge. I have tried restarting the machine, windows updates, discharging the battery, trying a different charger (this charger lets the machine turn on, but the top right of the device gets real hot).
You shouldn't use compatible "no brand" chargers with your machine...If it gets hot that may be a symptom of other problems, such as overcharging batteries. Your device is still on warranty? Try contacting the store where you bought it.