I have a HP Pavilion model a6113w desktop computer. Last week I added 2 new 1gb memory strips to my existing 2 gb of memory. Everything booted and ran correctly. I turned the computer off and didn't try to turn it back on for the week. When I tried to turn it on today, the "start" button light just flashed and everything went dead. I removed the new memory sticks and tried to start the computer again. Got the same result. Can anyone tell me where to start looking for the problem?