Macs refuse to use all cores for batch renders (Maya 2011)

[rsimon21]

Whenever I am trying to render in a mac lab, I find that around 75% of the macs simply refuse to use their full computing power (ie: 4/4 cores reading as 100% use). What happens is I start a render, then come back in 5 minutes to find that maybe one core is at 80% and the rest are at 6%. Forcing 4 threads helps, but it is still finnicky. Is there a way around this? or do I have to consistently watch them like a hawk?