I've had my very trusty E520 since about 2007, and it's served me well through the years. However today I encountered something weird: the power button on the front was flashing a sort of amber colour. I did some searching and found it could be a problem with the PSU, but I did the paperclip test and the fans started and such. After this I assumed it wasn't a PSU problem, but the light still flashes. Any idea why?

An additional note, I moved the computer recently. Could this have shaken something out of place inside?

Any response would be great. Thanks.