Performance will always use the max cpu all the time.
On-demand will use the minimum clock when the phone isn't doing anything (sleeping, just sitting there not running apps, etc.), the second you hit something, or receive a call, or do anything, it will instantly bump up to your max clock speed for optimum performance. You should be using on-demand for battery life.
The only profiles you need are
-default (when your using your phone)
-sleep/standby (when you're not using your phone)
-Max Temp/emergancy shutdown (should be around 40-45 celcius) I haven't seen a rom that has a temp sensor for the actual processor, but those are good general temps to down clock at for the battery. If it hits that temp, make it clock way down to allow it to cool off, like 2xx.
Thanks i just put mine to all of your settings.
Whats your MFLAP with 710? and Do other ROMS handle OC different? I was thinking of getting Ic3 v2.7
The rom doesn't determine the overclocking, it's all related to the kernel. The only difference as for handling is if you have a low voltage kernel, which can be less stable, but bring increased battery life (I haven't seen any out for the eris yet). Other kernel limitations are the max clock (the average is 768 being stable), some kernels stop you at 710, others go to 8xx. Different roms include different kernels, so you'll have to do some research.
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