Does QNX call the HLT instruction in its default idle loop for x86?  I found this response for one of the other posts 
but it doesn't give any information regarding x86 behaviour.

"A little of both. By default (you don't use the procnto -h switch), the idle loop will invoke a halt() function when it
 
runs. On PPC600 family chips (you didn't say which family you're interested in, but most of the Freescale chips are 
600's) the halt() function looks at the PPC_CPU_HW_POW bit in the cpuinfo section of the system page and, if set, will 
turn on the MSR[POW] bit. That typically puts the CPU into a lower power mode."


Also is there any info on timings for exiting low power states in QNX?

Is there any way of disabling cores?