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Power7 - Big Blue eye on UNIX

Four server preemptive launch

The mount

Like the prior generations of Power-based machines from IBM, the CPUs are mounted on processor cards that mount vertically into the system motherboards. Each processor card has sockets for the Power processors and slots for the main memory. I/O subsystems and external peripherals plug into the system board, which links out to the processor card through a backplane. (Generally speaking, this is the same sort of design that is expected with Intel's future "Becton" Nehalem-EX Xeon processors for multiprocessor SMP machines).

Like IBM's high-end System x servers, which can scale outside of the box using NUMA-like clustering (thanks to some technology Big Blue got when it bought Sequent Computer Systems in July 1999 for $180m). Up to four Power server nodes can be linked into a single system image for AIX, i/OS, or Linux using this interconnect. This interconnect is not available on every machine, and customers pay a premium for the scalability that comes from this interconnect.

The first new machine in the Power7 family of systems is the Power 750, which is the follow-on to the midrange Power 550 that was based on the Power5 and Power6 generations of chips. The Power 750 comes in the workhorse 4U chassis that IBM has had since 2004, but it has been modified to allow for up to eight front-mounted, small form factor disk or SSD drives. That 4U chassis can be configured as a rack or tower server and has room for up to four processor cards, each with 16 DDR3 main memory slots and each with a single processor socket.

This box has the widest variety of Power7 processor options among all of the machines announced thus far. One option has six-core Power7s running at 3.3 GHz, another uses eight-core processor cards that run at 3 GHz or 3.3 GHz. There is a top-end machine that only comes with four processor cards with all 32 cores turned on and running at 3.55 GHz. There seems little doubt that this box will carry the heftiest price.

The Power 750 offers from 8 GB to 512 GB of main memory expansion, with a maximum of 128 GB per processor card using 8 GB DDR3 DIMMs. The box has three PCI-Express and two PCI-X slots peripheral slots and a single GX+ adapter slot, which is used to hook remote I/O drawers (based on a modified InfiniBand link that IBM calls 12X) or graphics cards into the machine. The Power 750 can have four 12X I/O drawers using PCI-Express slots or twice as many using PCI-X drawers. With all of the I/O drawers in the box, the Power 750 can have 584 disk or SSD drives directly attached to it.

The Power 755 is a version of the Power 750 server that is tweaked specifically for supercomputing workloads (and maybe for parallel database clusters running IBM's DB2 PureScale software, but the company has not said). The Power 755 only comes with the four processor cards in the box loaded with 3.3 GHz cores and all 32 cores are activated. This machine can only have 64 GB of memory per processor card, however, which means memory tops out at 256 GB. Other than that and the fact that this machine only supports AIX and Linux, it looks just like a Power 750.

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