|Get the manuals at dell.|
Are you sure the F2 is the bios key?
Sometimes older motherboards had a fuse on the keyboard. If you plugged it in with power on you could have blown the fuse. It might be labled F1 or R1 and may not look like a fuse at all. Almost always near the keyboard connector.
Try different keyboard.
Reset bios by removing the cmos battery.
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