Question : Problem: laptop motherboard short

Dell XPS M1210. Problem:The power adapter won't power or charge the system.
Replaced the motherboard.   One week later the power adapter can't power or charge the system.
The power adapter is new (purchased in Jan. 09). when you plug the power adapter into the wall outlet the green light is solid, but when it is connected to the power port on the laptop the green light blinks then goes off. This happens whether the battery is in the machine or out.
I tried diffferent wall outlets with the same result.
What do you suggest I do next?

Answer : Problem: laptop motherboard short

i called tech support @ Dell and also did a web search stating the power adapter's behavior: found out that it means the motherboard has a short.