The max temp for your APU is 71.3°C, so yeah 80°C is too high.
Two things:
1. Measuring the temp for AMD APU's is different than Intel. Read up on how to correctly measure your APU's temps
http://www.tomshardware.com/faq/id-2122665/understanding-temperature-amd-cpus-apus.html
2. These things run hot with low thermal ceilings so it may be time to take the stock cooler off and reapply the compound. I like NT-H1 from Noctua but there are a ton of them out there and most fall within a degree or two of each other in performance.
Read up on the ins and outs of thermal compound and how to apply here
http://www.tomshardware.com/reviews/thermal-paste-heat-sink-heat-spreader,3600.html
http://www.tomshardware.com/reviews/thermal-paste-performance-benchmark,3616.html