Dell PowerEdge MX7000 Direct Orthogonal Connectors User's Manual

Direct from Power Edge Product Group Development

Power Edge MX7000 Direct Orthogonal Connectors

Modular systems (such as the Dell EMC Power Edge M1000e blade enclosure) integrating both compute/storage modules and switch (I/O) modules require an intricate method of interconnection within the chassis. A traditional interconnect

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architecture contains vertical compute/storage modules and horizontal switch

Ray Heistand modules, and a midplane enabling interconnection between these modules, as

Tad Walsh shown in Figure 1 below:

SUMMARY The trend of increasingly higher- power processors and DIMMs creates challenges for traditional midplane architectures, particularly with regard to airflow and cooling, high speed signal transmission, and power delivery.

The new Power Edge MX7000 modular platform eliminates the midplane and instead uses Direct Orthogonal Connectors for internal interconnection of compute, storage and switch modules.

Figure 1: A traditional interconnect architecture using a midplane for interconnection of compute Elimination of the midplane and switch (I/O) modules

greatly optimizes airflow and enhances cooling. Signal

transmission and power delivery A traditional midplane architecture such as the above has been an effective are also improved by this new, means of interconnect for many generations of servers, but a number of design innovative design. challenges have been apparent and need to be overcome. Airflow has been a key challenge. Proper airflow is critical in order to ensure cooling of the compute modules, especially with current and future systems with high-power processors and DIMM’s. One attempt to resolve this has been to incorporate vent holes into the midplane to allow airflow. However, due to signal and power routing within the midplane, properly sized and effective placement of the vent holes is not always feasible. Moreover, signal integrity (SI) may be impacted when routing high speed signal traces long distances within the midplane. Even the use of Low Loss PCB material (such as Megtron 6) for high speed signal traces has limitations.

Consequently, in the development of the Power Edge MX7000 Modular Chassis, the elimination of the midplane was a key design goal to improve airflow and signal integrity. To accomplish this, the implementation of Direct Orthogonal Connectors was selected to provide the interconnection between compute

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