IBM Power 720 - POWER7+ Processor and Intelligent Energy; Comparison of the POWER7+, POWER7, and POWER6 Processors

50 IBM Power 720 and 740 Technical Overview and Introduction
򐂰 Small physical footprint
The performance of eDRAM when implemented on-chip is similar to conventional SRAM
but requires far less physical space. IBM on-chip eDRAM uses only one-third of the
components used in conventional SRAM, which has a minimum of six transistors to
implement a 1-bit memory cell.
򐂰 Low energy consumption
The on-chip eDRAM uses only 20% of the standby power of SRAM.
2.1.6 POWER7+ processor and Intelligent Energy
Energy consumption is an important area of focus for the design of the POWER7+ processor,
which includes Intelligent Energy features that help to dynamically optimize energy usage and
performance so that the best possible balance is maintained. Intelligent Energy features, such
as EnergyScale, work with IBM Systems Director Active Energy Manager™ to dynamically
optimize processor speed based on thermal conditions and system utilization.
2.1.7 Comparison of the POWER7+, POWER7, and POWER6 processors
Table 2-2 shows comparable characteristics between the generations of POWER7+,
POWER7, and POWER6 processors.
Table 2-2 Comparison of technology for the POWER7+ processor and the prior generations
Characteristics POWER7+ POWER7 POWER6
Technology
32 nm 45 nm 65 nm
Die size 567 mm
2
567 mm
2
341 mm
2
Maximum cores 882
Maximum SMT
threads per core
4 threads 4 threads 2 threads
Maximum frequency 4.3 GHz 4.25 GHz 5.0 GHz
L2 Cache 256 KB per core 256 KB per core 4 MB per core
L3 Cache 10 MB of FLR-L3 cache
per core with each core
having access to the full
80 MB of L3 cache,
on-chip eDRAM
4MB or 8MB of FLR-L3
cache per core with
each core having
access to the full 32 MB
of L3 cache, on-chip
eDRAM
32 MB off-chip eDRAM
ASIC
Memory support DDR3 DDR3 DDR2
I/O bus Two GX++ Two GX++ One GX++
Enhanced cache
mode (TurboCore)
No Yes
a
a. Only supported on the Power 795.
No