Have you tried the airflow diagram as below. Blue for intake while red for outlets.

The most important part is front intake, top exhaust. Fans on H80 best to be installed blowing out immediately and not blown into the case.

Try in closed case.

What were you expecting with idle temps? Blame ambient temperature + OC
Under normal conditions, OCing will also lead to higher idle voltages, which in turn lead to higher idle temperatures.

Even so, 40c isn't a dangerous temperature.

Maybe your ambient temperature is 2c higher, so normal for your temperature to be 2c higher. Also, you may have stuff running in the background, using small amount of cpu (1-5%) which can also contribute to a little bit higher temperature.

What does not function? RPM reading? Your fans are connected to mobo or power supply?

Don't worry so much on your idle temperature. As long as it isn't 50-70 for idle, it should be fine.

CPU-Z. Memory tab will show ~800 for DRAM Frequency = 1600Mhz

What ram are you using? If it has XMP 1600, go bios and load the XMP profile (not really sure how to do - check manual or do internet search)

corsair dominator1600mhz

That near enough to 1600Mhz.