Chinese no-name YXY-FGD-50W
White goo under the LED metal backing, only covering about 1/3 of the
area, as originally placed blob , not fully splurged. Bowing of the
metal at rear of the LED array , probably at original placement due to
blob shape of the goo , only maybe worsened in use. So heatsinking via
the periphery only , ie delayed heatsinking.