150
Intel
82865G/82865GV GMCH Datasheet
Functional Description
5.2.1
DRAM Technologies and Organization
Supported DRAM technologies and organizations include:
All standard 128-Mb, 256-Mb and 512-Mb technologies and addressing are supported for x16
and x8 devices.
All supported devices have 4 banks.
The GMCH supports page sizes. Page size is individually selected for every row
— 4 KB, 8 KB, 16 KB for single-channel mode.
— 8 KB,16 KB, and 32 KB in dual-channel mode
The DRAM sub-system supports a single or dual-channel, 64 b wide per channel
There can be a maximum of four rows populated (two double-sided DIMMs) per channel.
Mixed mode DDR DS-DIMMs (x8 and x16 on same DIMM) are not supported
By using 512-Mb technology, the largest memory capacity is 2 GB per channel
(64M x 8b x 8 devices x 4 rows = 2 GB)
By using 128-Mb technology, the smallest memory capacity is 64 MB per channel
(8M x 16b x 4 devices x 1 rows = 64 MB)
5.2.2
Memory Operating Modes
The GMCH supports the following modes of operation
Single-channel mode (SC).
— Populate channel A only
— Populate channel B Only
— Populate both channel A and B.
Dual-channel lock step mode (DS).
— DS linear mode.
— DS tiled mode. (internal graphics mode)
The GMCH supports a special mode of addressing – Dynamic Addressing mode. All the above-
mentioned modes can be enabled with/without Dynamic addressing mode enabled.
Table 18
summarizes the different operating modes GMCH memory controller can operate.
NOTE:
1. Special cases – need to meet few requirements discussed in
Section 5.2.2.1
.
Table 18. GMCH Memory Controller Operating Modes
Mode Type
Dynamic
Addressing Mode
Non-Dynamic
Addressing Mode
SC Mode
Channel A Only
Yes
(1)
Yes
Channel B Only
Yes
(1)
Yes
Both Channel A and B
Yes
(1)
Yes
DS Mode
Linear
Yes
Yes
(1)
Tiled
Yes
Yes
(1)