onkyo sr-608 and wattage use of 7.1 speakers

[edward0829]

I have a question about the above receiver. I currently have klipsch 500 hd speakers and subwoofer attached as well as 2 sony ssr-6000 tower speakers. Because this is 7.1 setup with klipsch rated at 100 w per speaker and the sony ones at 180 or so should I worry about over burdening the onkyo receiver? How can I figure out what the wattage usage is now? Or is there no real need to worry? At maximum I set the volume to 55. Thanks!