did you unplug power cord from the computer before adding the RAM? modern computers remain powered even though they are turned off. replacing components with the power on can damage large parts of your system. you have to disconnect the power cord first.

assuming that you had disconnected the power, if you have removed the added RAM and it still doesn't come up, you've fried something anyway, probable CPU or the motherboard. if you haven't removed the new RAM, do so, with the power disconnected first.

Herb....