Sizzling hot backplate 1080

[giveUSAback2UK]

Hi,
Maybe a noob question, but I've never touched the backplate of a running GTX 1080 until the other day.
I have a new crazy rig I'm testing and overclocking to the max. My temps are high (57 degree GPU) but my backplate (aftermarket fullcover EK backplate with thermalpads) is sizzling hot. Getting worried. Can't touch it for more than a few seconds. Is this normal? Should I be concerned? There is some airflow from a fan directed at the card from below, but still...

Secondary question is what you guys think of a single 140 mm rad that I could fit in - would it make much of a difference on gpu temps? I might be a tad low on fanpower and rads as it is only a 30 mm thick rad.

My rig:
GTX 1080 Titan X Pascal (overclocked to to max)
Hardware Labs GTS 360
TT Plus fans (1500 rpm) x 3
Open air case

Ambient temperature: 22 degrees.
Water-temperature: 30 degrees (idle) / 46 degrees (heavy oc)
GPU temp: 32 degrees (idle) / 57 degrees (heavy oc)

I'm not sure I can trust the temps for water 100% as it is connected on the GPU inlet and could be heated up from the actual block.

Many thanks for input.

 

[giveUSAback2UK]

Thanks for your input guys. Was worried about the VRam.
I have never run anything on 24/7 with maxed gpu with only 360 rads, but couldn't resist as I'm mining crypto for fun.

Was thinking of even doing some DIY and connecting heatpipes to the waterblock

But I'm happy to hear the temps are okay - I usually opt for bursts in GPU usage (or headset when gaming) so the gpu never got this hot in other rigs.

The watertemp is a bit of a concern.
Thinking of adding a 140 (30 mm rad), but still not sure if it would do any good.