CLR_CMP_CNTL
regw(sc, CLR_CMP_CNTL, 0);
regw(sc, CLR_CMP_CNTL ,0); /* no transparency */
regw(sc, CLR_CMP_CNTL, 0); /* no transparency */
regw(sc, CLR_CMP_CNTL ,0); /* no transparency */
regw(sc, CLR_CMP_CNTL, 0); /* no transparency */