Dell M820 owner manual 1600 MT/s

System Capacity	DIMM Size (in	Number of	Organization and	DIMM Slot Population
(in GB)	GB)	DIMMs	Speed
32	4	8	2R x8, 1333 MT/s	A1, A2, A3, A4, B1, B2, B3,
			2R x8, 1600 MT/s	B4
64	4	16	2R x8, 1333 MT/s	A1, A2, A3, A4, A5, A6, A7,
				A8, B1, B2, B3, B4, B5, B6,
				B7, B8
64	8	8	2R x4, 1333 MT/s	A1, A2, A3, A4, B1, B2, B3,
			2R x4, 1600 MT/s	B4
96	4	24	2R x8, 1333 MT/s	A1, A2, A3, A4, A5, A6, A7,
				A8, A9, A10, A11, A12, B1,
				B2, B3, B4, B5, B6, B7, B8,
				B9, B10, B11, B12
96	8	12	2R x4, 1333 MT/s	A1, A2, A3, A4, A5, A6, B1,
			2R x4, 1600 MT/s	B2, B3, B4, B5, B6
128	8	16	2R x4, 1333 MT/s	A1, A2, A3, A4, A5, A6, A7,
			2R x4, 1600 MT/s	A8, B1, B2, B3, B4, B5, B6,
				B7, B8
128	16	8	2R x4, 1333 MT/s	A1, A2, A3, A4, B1, B2, B3,
			2R x4, 1600 MT/s	B4
160	8	20	2R x4, 1333 MT/s	A1, A2, A3, A4, A5, A6, A7,
			2R x4, 1600 MT/s	A8, A9, A10, B1, B2, B3,
				B4, B5, B6, B7, B8, B9, B10
160	16 and 8	12	2R x4, 1333 MT/s	A1, A2, A3, A4, A5, A6, B1,
				B2, B3, B4, B5, B6

2R x4, 1600 MT/s

192	8	24	2R x4, 1333 MT/s
			2R x4,	1600 MT/s
192	16	12	2R x4,	1333 MT/s

NOTE: 16 GB DIMMs must be installed in the slots numbered A1, A2, A3, A4, B1, B2, B3, and B4 and 8 GB DIMMs must be installed in slots A5, A6, B5 and B6.

A1, A2, A3, A4, A5, A6, A7, A8, A9, A10, A11, A12, B1, B2, B3, B4, B5, B6, B7, B8, B9, B10, B11, B12

A1, A2, A3, A4, A5, A6, B1, B2, B3, B4, B5, B6

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