For ND-2500A possible Speeds are: with "-RW"-----4x, 2x and 1x with "-R"-------8x, 6x, 4x and 2x, with "+RW"-----4x and 2.4x with "+R"-------8x, 6x, 4x and 2,4x with "CD-R"-----32x, 24x, 16x and 8x with "CD-RW"- --16x, 10x and 4x.