Is a Thunderbolt cable usable between a MacBook and a non-Apple external display?
No.  You cannot use a Thunderbolt cable to connect to a mini Display Port (mDP) monitor.

The reason you are seeing the monitor shut off is because you are sending it Thunderbolt AND Display Port signaling.  Remember, Display Port is, for a lack of a better word, embedded within the Thunderbolt signal.



Just using pin 1 for example, the Display is expecting ground while TB is sending HV Input.  

This is why you need a mini Display port cable when hooking up a monitor and a Thunderbolt cable when hooking up a Thunderbolt device.