Just got a Raspberry Pi B starter kit with an 8GB SD card pre-installed with NOOBS, .
When I power it up all I get is the red light, lights up and nothing happens. 
I tried two different tv and cables and still nothing.
I had the exact same problem with my PI when I powered it up, for a while I thought it was broken until I found out that I was acting that way because when the PI is booting it is set to the HDMI output so if you are using a different output port nothing will be displayed. To change the output connect a keyboard and press the keys from 1-4 but wait a few seconds between pressing the keys to see if the correct key has been pressed to activate the video output that you are using once your screen activates remember the key that you just pressed for the next time that you change the ports. The key to press for the yellow composite video jack is either 3 or 4 if that is the port you are using. I hope this helped you, if you have anymore problems just ask.
I had the exact same problem with my PI when I powered it up, for a while I thought it was broken until I found out that I was acting that way because when the PI is booting it is set to the HDMI output so if you are using a different output port nothing will be displayed. To change the output connect a keyboard and press the keys from 1-4 but wait a few seconds between pressing the keys to see if the correct key has been pressed to activate the video output that you are using once your screen activates remember the key that you just pressed for the next time that you change the ports. The key to press for the yellow composite video jack is either 3 or 4 if that is the port you are using. I hope this helped you, if you have anymore problems just ask.
I'm using the HDMI port, I have left it on for 5 minutes and I still get nothing and only the red light is on on the pi.
Just try pressing the number keys one at a time and waiting a little while between keys that should switch it to HDMI eventually.