There are 4 cards in the MX series. MX460, MX440, MX440SE, MX440 with AGP8X support and MX420.
The MX440 and the MX440SE that you're talking about are based on the NV17 chip. Here are the specifications.
GF4MX440 - 1.1Bilion TexelsPS, 34Milion TrianglesPS, 6.4GB/sec of Memory Bandwidth, AGP4X...