Generally for all Neptunes and Titans I recommend good quality cables and connectors to keep them running reliably. Like a good 16AWG y-cable. I have mine done by Shakmods, running non-stop since September @ 500MHz "burn-less" 
BONUS NEPTUNE OWNERS BEWARE!
As mentioned before, the Bonus Neptunes do not have thermalpads on PWM modules and the included fans do not provide enough airflow.
But here comes the good part, there are other "bonus" features:
Badly installed heatsink with bad contact to ASIC heatspreader
http://abload.de/img/r00203371uol1.jpg
Someone during assembly left a Torx screwdriver head inside the Neptune Cube! Shorting circuits FTW!
http://abload.de/img/r0020338xwscl.jpg
I have never seen such an amateur work, and I am deeply disappointed. Apart from the ASIC chip itself, KNC machines look like a high-school science project.
BONUS NEPTUNE OWNERS BEWARE!
As mentioned before, the Bonus Neptunes do not have thermalpads on PWM modules and the included fans do not provide enough airflow.
But here comes the good part, there are other "bonus" features:
Badly installed heatsink with bad contact to ASIC heatspreader
http://abload.de/img/r00203371uol1.jpg
Someone during assembly left a Torx screwdriver head inside the Neptune Cube! Shorting circuits FTW!
http://abload.de/img/r0020338xwscl.jpg
I have never seen such an amateur work, and I am deeply disappointed. Apart from the ASIC chip itself, KNC machines look like a high-school science project.