John J. Loparco

Packaging design of the IBM system z10 enterprise class platform central electronic complex

The IBM System z10™ Enterprise Class mainframe addresses the modern data center requirements for minimizing floor space while increasing computing power efficiency. These objectives placed challenges on the z10™ packaging design as a result of significantly increased demand on system packaging density, power delivery, and logic and power cooling efficiency compared with the recent IBM System z9® and z990 mainframe generations. Several innovations were implemented to successfully meet these challenges: a more powerful multichip module (MCM) that delivers denser computing capability and a 64-way system; a vertically mated processor unit (PU) book structure that achieves a more efficient thermal implementation and a higher signal bandwidth between processors; and a PU book-centric dc-dc power delivery design that is more efficient. This paper presents the key elements to achieve this design: the novel mechanical load transmission paths and the connector technologies for the MCM, PU book, I/O, and power regulation components; an innovative cooling and thermal design that includes component-level tolerance of failures; and improved power delivery and power code developments to maximize the overall z10 compute efficiency.

Packaging the IBM eServer z990 central electronic complex

The z990 eServerTM central electronic complex (CEC) houses four multichip-module-based processor units instead of one, as in the previous-generation z900 eServer. The multichip module (MCM) input/output pin density in z990 processor units is more than twice that of the MCMs in z900 processor units. This increase in packaging density and the consequent tripling of the current drawn by the processor units were accommodated by the first-time use of land grid array (LGA) MCM-to-board interconnections in an IBM zSeries® eServer. This was done by using innovative refrigeration cooling of the MCM with air cooling as backup, and by a new mechanical packaging and power distribution scheme. This paper describes the mechanical engineering of the CEC cage, the LGA MCM-to-board interconnection scheme, and the mechanical isolation of the MCM evaporator-heat-sink mass from the LGA contacts. The paper also describes the electrical power and the cooling solutions implemented to meet the more demanding requirements of the denser CEC package.

Mechanical packaging, power, and cooling design for the IBM z13

The system-level packaging of the IBM z13™ supports the implementation of a new drawer-based Central Processor Complex (CPC). Departing from previous IBM z Systems™ designs, the introduction of distributed land-grid-array (LGA) attached single-chip modules (SCMs) required new mechanical, power, and cooling designs to address specified performance requirements and to provide enhanced reliability, availability, and serviceability (RAS) attributes. Building upon the designs created for the IBM zEnterprise® BC12 (zBC12), new CPC drawer and frame mechanical designs were created to significantly increase overall packaging density. Similar to its predecessor, the IBM zEnterprise EC12 (zEC12), the z13 utilizes water-cooling of the processors, but in contrast to the single input and return flow used to cool the multi-chip module (MCM) in the zEC12, the z13 accomplishes its processor cooling using a flexible hose internal manifold design that provides parallel input and return fluid flow to each SCM. The use of flexible hose also enabled SCM field replacement, new to high-end IBM z Systems. A new internal cooling loop unit and an updated external (building-chilled) modular water-conditioning unit were designed utilizing customized water delivery manifold systems to feed the common CPC drawer design. Revised power delivery and service control structures were also created to address the distributed nature of the z13 system design.