Review of the second: http://www.pcmag.com/article2/0,2817,2403745,00.asp
That seems more than you need. I'd stick to the cheaper one. A nice consumer-oriented model.
Just to be sure it's the port of the router that's the culprit (and not the port on the desktop or the cable), did you try:
1. The other 3 ports on the router?
2. To connect the desktop directly to the modem (plug the cable that now goes from the modem to the router directly in the desktop)
3. Another cable?
4. Connect the laptop wired in stead of the desktop to see of that also says it's unplugged?
It would be a pity to spend $50 if it isn't necessary.
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