The CPU temp being 80C is far to high but I would expect it to be only 10C higher than the core temps so I suspect its a faulty sensor, assuming it is the temps are fine. Ther motherboard temp is fairly high but not problem high.
Looking at HWMonitor, The TMPIN2 80c reading never changes does it ? That I believe is a bum NB reading, Asus boards will report it as a constant 128c like mine. I believe TMPIN0 is your MB temp, it should be a couple degrees over your ambient and only fluctuates a couple of degrees. TMPIN1 should be your cpu temp, idling at 34c and rising to 51c while stressing. Your core temps vary about the same as my proc., about 10c under cpu socket temp at idle and 5c under socket temp at load.
Your temps are fine at 50C. TMPIN1 is your CPU temp. That is the temp that you can take up to 62C so you have a bit of headroom before you reach your limit. Try upping the voltage to 1.475 which is the turbo core voltage and put your overclock to around 3.75-3.8 ghz. You may be able to keep your temps under 62C and remain stable.
I'm amazed you can run 3.5Ghz at 1.3v. I need at least 1.375 to get away with that on my 1055T.