Dell 1720 XL Printer Power Failure

Yesterday when I attempted to print a ninety seven page portable document file, after printing the first twenty pages properly, my printer began to print pages that retained the format of the document, but replaced the text with seemingly random letters.  I had suffered a kindred problem some days earlier when it printed numerous pages with only a single line of seemingly random symbols in the upper margin of the pages.  The 'cancel' button seemed to have no effect, so I turned the power off to cease the printer. 

After I cancelled the printing of the document from my computer and cleared a partially printed page from the printer, I switched the power toggle back into the 'on' position, but nothing happened.  No sound was produced by the printer and no lights were lit; it appeared for all intents and purposes as though it were disconnected from power.  The icon under 'Printers and Faxes' indicates that it is offline and disconnecting or reconnecting the USB cable yields no respones.  I have disconnected it from power and my computer several times, connected it through various different outlets and ports, removed and replaced the toner cartridge and uninstalled, then reinstalled printer and its drivers.  None of these measures have had an effect.  Whenever I switch the power toggle, I can hear a muffled click, but nothing happens.

I am using Windows XP Professional 64-bit edition and the printer is quite new as it was bought late last year to replace an older printer.