OMAP3530 operating temperature range

We are using an OMAP3530 chip and we are having problems operating at higher temperatures and clock speeds.  

What is TI's method for testing operating range?  

Also it would be beneficial to know how a commercial chip classification is determined and how an extended temperature chip classification is determined?

We would like to see if we can test our chips to see if their operating range is similar to specifications or if we have done something with our design to change their operating range.  We would like to know how they were originally tested so that we can test them similarly.   Any help with this is greatly appreciated.  

Thanks,