Raspberry Pi b+ heats up but won't start. What is the reason?

Question

Iron

The usb-rs232 cord came to me and I began to poke it. At one point, I compared the inscription 5v on the chip in the cord and 5v on the pin and immediately connected it. Model B quietly began to feed on this and continued to work.
When the turn came to B+, I connected in the same way:
pin2 --
5v pin6 -- gnd
pin8 -- txd
pin10 -- rxd.
The device immediately turned off and no longer starts, while the CPU heats up to incredible temperatures in seconds.
Is it curable?

Answer 1

If the lace is disconnected, and the percentage is wildly heated, then most likely there is nothing to help.

Answer 2

Looks like it will have to be buried.

Answer 3

If it gets hot, then it's a short circuit. Most likely to be thrown out.