Yeah the temperature is veeery important. I can't tell you how many people have gotten random restarts and not know the cause when it was simply heat issues. It can also bring down the performance of your components so you should try and keep it low at all costs. I don't know any programs off the top of my head since my mobo came with one for me to use. But I'm sure if you google it then you'll find one and if worse comes to worse you can always just check it in the BIOS.
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