(thing) by novalis Thu Apr 20 2000 at 12:46:24
MMX instruction to subtract packed words with unsigned saturation.

A MMX register or 64 bit memory location is subtracted from to a MMX register, word-wise. Negative words are clamped to 0.

Compare PSUBUSB, PSUBUSD, PSUBSW, PSUBW.
I like it!