We have an Dell Inspiron 1521. Everything runs fine except that external displays are no longer getting a signal. It just stopped working the other day. If you get the VGA cord just right it will get a signal through for a second, but then it goes away. I figure there's something in there but can't see it. Does anyone know how to clean these things or if it's possible to just replace that part without a whole new computer?
As far as cleaning the port goes, blowing it out with a can-o-air usually works pretty well. Have you checked to ensure that all the pins still exist in your monitor's cable?
As for replacing it, this piece is soldered to the motherboard, and is usually fairly expensive to have replaced, but it may be done at a local shop.
Have you ensured that the external port is enabled? Dells have a shortcut key (F7 or F8 as I recall) which turns on/off this display. You have to hold down Fn to do it, though. Tapping it slowly should cycle from Internal => External + Internal => External => Repeat.