I have a new RB750 that upon boot will flash all LED's on the interface section, blink #1 briefly (as that's the only connection plugged in), and then blink off.

I've tried holding the reset button down while power it up, the ACT light will blink, and then I release, but none of the lights will ever turn on. I've tried every port.

Have you try connect with this routerboard via Winbox?

Have you disabled the firewall on you r PC or laptop?

Have you try connect with this routerboard via Winbox?

Have you disabled the firewall on you r PC or laptop?

Yes, I setup many of these with the same computer.

Try first netinstall procedure http://www.wirelessinfo.be/index.php/mi ... etinstalle

Change power supply if this not works
Take contact with Mikrotik on
support@mikrotik.com or contact your seller.