Firmware Change Update On Sony Kdl50w800c Hot High Quality Review
If your TV is connected to Wi-Fi or an Ethernet cable, this is the standard method.
Updates often include "under-the-hood" improvements that reduce lag and speed up the interface.
Leo lunged for the plug.
If your TV isn't connected to the internet, or if the automatic check says your software is "up to date" even though a newer version exists online, you can force the update via USB. Preparation Checklist Drivers and Software updates for KDL-50W800C - Sony
Causes and risks
The new firmware appears to disable some aggressive downclocking that previously kept the MediaTek MT5890 cooler. Sony likely did this to improve UI smoothness. Less throttling = more heat = "hot" TV.