TPACPI_Q_IBM('1', 'Y', TPACPI_BRGHT_Q_EC),      /* T43/p ATI */
 
        /* Models with ATI GPUs that can use ECNVRAM */
-       TPACPI_Q_IBM('1', 'R', TPACPI_BRGHT_Q_EC),
+       TPACPI_Q_IBM('1', 'R', TPACPI_BRGHT_Q_EC),      /* R50,51 T40-42 */
        TPACPI_Q_IBM('1', 'Q', TPACPI_BRGHT_Q_ASK|TPACPI_BRGHT_Q_EC),
-       TPACPI_Q_IBM('7', '6', TPACPI_BRGHT_Q_ASK|TPACPI_BRGHT_Q_EC),
+       TPACPI_Q_IBM('7', '6', TPACPI_BRGHT_Q_EC),      /* R52 */
        TPACPI_Q_IBM('7', '8', TPACPI_BRGHT_Q_ASK|TPACPI_BRGHT_Q_EC),
 
        /* Models with Intel Extreme Graphics 2 */
-       TPACPI_Q_IBM('1', 'U', TPACPI_BRGHT_Q_NOEC),
+       TPACPI_Q_IBM('1', 'U', TPACPI_BRGHT_Q_NOEC),    /* X40 */
        TPACPI_Q_IBM('1', 'V', TPACPI_BRGHT_Q_ASK|TPACPI_BRGHT_Q_EC),
        TPACPI_Q_IBM('1', 'W', TPACPI_BRGHT_Q_ASK|TPACPI_BRGHT_Q_EC),