RISERS ARE EVIL CREATURES--

Your riser looks ok, but there are many variations that look the same.  I use a riser that is v006c or v007, depending on the manufacturer or the distributor.  It has a PCIe electrical connector rather than a molex.  I started changing out all my old, skinny risers when I noticed the thin power connectors melting.

I cannot give much advice for which riser, but switching out a riser will often solve the problem.  The PCIe connector is more sturdy, thicker, and less subject to heat damage than a thin molex, once standard for floppy drives. The larger molex on your riser is often difficult to connect because the pins push out-of-position.
 
Keep spare risers handy, find a good source.  I am in the USA and shop Amazon.  MintCell is an Amazon retailer that has good risers, but even new ones fail.

Good Luck!       --scryptr