RESEARCH & DEVELOPMENT STANDARDS &
REGULATIONS
COM-HPC/Client module will also
come in two footprints, measuring
120x120 mm and 160x120 mm.
Primarily designed for use in highend
applications in the embedded
computing area, the Client module
– unlike the COM-HPC/Server module
– integrates video interfaces such as
DDI or eDP/MIPI-DSI for the control
of up to 4 high-resolution displays.
It further provides up to 2 GbE
interfaces for network connection via
NBASE-T.
In terms of power consumption,
COM-HPC/Client modules can be
classified as low-power components,
while COM-HPC/Server modules,
which are optimised for maximum
connectivity and workload
performance, have a correspondingly
high power draw. Hence the plan
is to supply up to 300W for the
Server modules and up to 200W
for the Client modules. The primary
connector reserves a remarkable 28
power pins on each COM-HPC module
for this purpose.
All COM-HPC modules can also
execute up to 64 PCIe lanes to the
carrier board and support PCIe up to
specification Gen 5.0, which allows
transfer rates of up to 32 Gb/s
per lane. This makes it possible to
connect several powerful GPGPUs.
For the physical connection between
the COM-HPC modules and the carrier
board, two connectors with 400 pins
also depend on such powerful edge
server solutions. The power grid can
then be divided into intelligent sub-
and microgrids, enabling the edge
server infrastructure to react instantly
and in real-time to power fluctuations
caused by current peaks or sinks.
All these new challenges are not
easily mapped with the existing COM
Express standard.
Is PCIe 6.0 also covered by the
specification?
Providing 32 Gbit/s per lane, COMHPC
will support PCIe Gen 5.0 with
up to 64 PCIe lanes to the carrier
board, and it will probably also be
able to cope with its successor, PCIe
Gen 6.0. But since PCIe Gen 6.0 will
not be fully ratified until 2021, there
may still be changes that make this
impossible.
Having said that, PCIe Gen 6.0
will definitely be backward compatible
to PCIe Gen 5.0. PCIe Gen 6.0 sets
the modulation from NRZ (non-return
to zero) to PAM4 (four-level pulse
amplitude modulation). While the
clock frequency stays the same, 2
bits are transmitted per clock instead
of only 1 bit. This technology has long
been used in MLC Flash memory.
Judging by the preliminary information
on PCIe 6.0, COM-HPC is also
equipped for this technology leap,
as the connector used is already
specified for 56 Gbps PAM4.
What is the time frame for the
standardisation of COM-HPC?
The pin-out definition was
launched last November.
Since then, the members
of the PICMG COM-HPC
committee have been able to
embark on first designs. The
final COM-HPC specification
is to be ratified in Q1 2020.
The first products, or at least
“previews” of the first COMHPC
modules, will probably be
presented by PICMG COM-HPC
committee members in that
quarter as well.
Christian Eder,
chairman of the
PICMG COM-HPC
technical subcommittee
each – so a total of 800 pins – are
available. With almost twice as many
pin connections to the carrier board
as COM Express, the COM-HPC
specification therefore also provides
considerably more interconnect
options.
What are the target markets for the
new class of modules?
The COM-HPC standard addresses
applications with exceptionally
high performance requirements,
such as those common in serverbased
applications for the harsher
environments, in edge infrastructures
for carriers and Industry 4.0
manufacturing, in the outdoor sector
and in vehicles of all kinds.
COM-HPC/Server modules will
be used wherever large amounts
of data have to be processed with
lowest possible latency – and where
forwarding the data for processing
in central clouds and sending them
back would take too much time.
An example of this is the
infrastructure for self-driving vehicles,
which requires very fast response
times and can therefore only be
implemented via a powerful edge
server layer at the edge of the cloud.
The power supply – which in
future will no longer be provided by
just a few large suppliers, but by an
increasing number of medium-sized,
small and even tiny suppliers – will
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