Originally Posted by DeadZeriousBass
Try them both ways and play around with it and find which way you like the best.
This is probably the best advice!
But to give you a bit more detail: in general, noise gates work more effectively before overdrives. An overdrive will amplify any noise coming from your bass, which often brings the noise closer to the volume level of your good signal. The closer the noise and good signals are, the harder it is for the suppressor to tell the difference between the two.
However, if the noise isn't originally coming from your bass, and is instead originating from the overdrive pedal, you would want the noise suppressor after the overdrive.
I hope I explained that alright. Make sense?