Sorry to give you so much, but you didn't give the exact model....
CM2X1024-6400
........................XMS640X v1.X...MICRON.......64Mx8...Rev.A
........................XMS640X v2.X...ELPIDA........64Mx8...Rev.E
........................XMS640X v4.X...QIMONDA.....64Mx8...Rev.B
........................XMS640X v5.X...PROMOS.......64MX8...90nm
........................XMS640X v6.X...NANYA.........64Mx8...Rev.B
........................XMS640X v7.X...PSC.............64MX8...90nm
CM2X1024-6400D
........................XMS640X v2.X...PROMOS........64MX8...90nm
........................XMS640X v3.X...ELPIDA..........64MX8...Rev.H
........................XMS640X v4.X...QIMONDA.......64MX8...Rev.C
........................XMS640X v5.X...MICRON.........64Mx8...Rev.D
CM2X1024-6400PRO
........................XMS640X v1.X...MICRON.......64Mx8...Rev.A
........................XMS640X v2.X...ELPIDA........64Mx8...Rev.E
........................XMS640X v3.X...QIMONDA.....64Mx8...Rev.B
........................XMS640X v5.X...NANYA.........64Mx8...Rev.B
CM2XP1024-6400C4
........................XMS640X v1.X...MICRON.........64Mx8...Rev.D
........................XMS640X v2.X...ELPIDA..........64MX8...Rev.H
CM2X1024-6400C4/C4DHX
........................XMS640X v1.X...MICRON.........64Mx8...Rev.D
........................XMS640X v2.X...PROMOS........64MX8...90nm
........................XMS640X v3.X...SAMSUNG......64MX8...Rev.C
........................XMS640X v4.X...QIMONDA.......64Mx8...Rev.C
........................XMS640X v5.X...ELPIDA..........64Mx8...Rev.H
........................XMS640X v6.X...PSC..............128Mx8
CM2X1024-6400C4D/C4DHX
........................XMS640X v1.X...MICRON.........64Mx8...Rev.D
........................XMS640X v2.X...PROMOS........64MX8...90nm
........................XMS640X v3.X...ELPIDA..........64MX8...Rev.H
........................XMS640X v4.X...QIMONDA.......64MX8...Rev.C
........................XMS640X v6.X...PSC..............128Mx8
CM2X1024-6400C4PRO
........................XMS640X v1.X...MICRON.........64Mx8...Rev.D
........................XMS640X v2.X...PROMOS........64MX8...90nm
........................XMS640X v3.X...ELPIDA..........64MX8...Rev.H
........................XMS640X v4.X...QIMONDA.......64MX8...Rev.C
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