I got my 3rd Raspberry Pi 3 B from Element14 in India and soon after I booted with Raspbian and within a few minutes, the HDMI display showed noise lines and finally the display totally failed. The Raspbian was working, as I could ssh into it. Subsequent reboots caused the HDMI to be blank, but system working with ssh. The "vcgencmd measure_temp" showed 44 and rising up to 50 very fast.
If I chill the Pi and then power on, I am able to get the display for about 5 minutes, and then when it heats up, and the display fails. With config_hdmi_boost=11 it works for a bit longer, but after sometime that too fails.
Issue seems to be that of SoC overheating. But I am puzzled not understanding which part of SoC reduces the signal strength that is going to HDMI with a "normal" heating level of SoC. I am in Kolkata and in March the normal room temperature is a bit hot!
Is there anything I can check before I try for a return of the board?
Thanks a lot to Raspberry Pi team.