Intel X3470 BV80605001905AJ User Manual
Product codes
BV80605001905AJ
Interfaces
22
Datasheet, Volume 1
2.1.3.2
Dual-Channel Mode—Intel
®
Flex Memory Technology Mode
The IMC supports Intel Flex Memory Technology mode. This mode combines the
advantages of the Dual-Channel Symmetric (Interleaved) and Dual-Channel
Asymmetric Modes. Memory is divided into a symmetric and a asymmetric zone. The
symmetric zone starts at the lowest address in each channel and is contiguous until the
asymmetric zone begins or until the top address of the channel with the smaller
capacity is reached. In this mode, the system runs with one zone of dual-channel mode
and one zone of single-channel mode, simultaneously, across the whole memory array.
advantages of the Dual-Channel Symmetric (Interleaved) and Dual-Channel
Asymmetric Modes. Memory is divided into a symmetric and a asymmetric zone. The
symmetric zone starts at the lowest address in each channel and is contiguous until the
asymmetric zone begins or until the top address of the channel with the smaller
capacity is reached. In this mode, the system runs with one zone of dual-channel mode
and one zone of single-channel mode, simultaneously, across the whole memory array.
2.1.3.2.1
Dual-Channel Symmetric Mode
Dual-Channel Symmetric mode, also known as interleaved mode, provides maximum
performance on real world applications. Addresses are ping-ponged between the
channels after each cache line (64-byte boundary). If there are two requests, and the
second request is to an address on the opposite channel from the first, that request can
be sent before data from the first request has returned. If two consecutive cache lines
are requested, both may be retrieved simultaneously, since they are ensured to be on
opposite channels. Use Dual-Channel Symmetric mode when both Channel A and
Channel B DIMM connectors are populated in any order, with the total amount of
memory in each channel being the same.
performance on real world applications. Addresses are ping-ponged between the
channels after each cache line (64-byte boundary). If there are two requests, and the
second request is to an address on the opposite channel from the first, that request can
be sent before data from the first request has returned. If two consecutive cache lines
are requested, both may be retrieved simultaneously, since they are ensured to be on
opposite channels. Use Dual-Channel Symmetric mode when both Channel A and
Channel B DIMM connectors are populated in any order, with the total amount of
memory in each channel being the same.
When both channels are populated with the same memory capacity and the boundary
between the dual channel zone and the single channel zone is the top of memory, IMC
operates completely in Dual-Channel Symmetric mode.
between the dual channel zone and the single channel zone is the top of memory, IMC
operates completely in Dual-Channel Symmetric mode.
Note:
The DRAM device technology and width may vary from one channel to the other.
Figure 2-1. Intel
®
Flex Memory Technology Operation
C H B
C H A
C H B
C H A
B
B
C
B
B
C
B
B
C
N o n in te r le a v e d
a c c e s s
a c c e s s
D u a l c h a n n e l
in te r le a v e d a c c e s s
in te r le a v e d a c c e s s
T o p o f M e m o r y
B – T h e la r g e s t p h y s ic a l m e m o r y a m o u n t o f th e s m a lle r s iz e m e m o r y m o d u le
C – T h e r e m a in in g p h y s ic a l m e m o ry a m o u n t o f th e la r g e r s iz e m e m o r y m o d u le
C – T h e r e m a in in g p h y s ic a l m e m o ry a m o u n t o f th e la r g e r s iz e m e m o r y m o d u le