COM-HPC Academy: COM-HPC Server Modules

December 16, 2020


In a previous blog, I discussed the client side of the new COM-HPC specification. Here, I’ll take a look at the server side. The standard is nearing its release date, with development of said standard being handled by PICMG, an organization whose charter is to promote open modular computing standards, mostly for the embedded computing segment.

COM Express, which is the current popular Computer-on-Module (COM) specification, has made some in-roads into the server space. But that’s not really what COM Express was intended for. COM-HPC eliminates the shortcomings associated with COM Express for server applications. That begins with the power consumption. COM-HPC allows the resident CPUs to draw up to 150 W, which is enough for most applications. Remember that there’s only so much space available on the module, so the number of CPUs is limited. Hence, 150 W should suffice.

Two server form factors are specified for COM-HPC, D and E. Form factor D measures 160 by 160 mm, while size E comes in at 200 by 160 mm. In addition, size D accommodates four DIMM modules, while E can handle up to eight. The module’s area allows for sufficient cooling as well, even when the power is ramped up to the maximum 150 W.

Higher Performance for Compute-Intensive Applications

You’ll need these processing and memory capabilities as Industry 5.0 and artificial intelligence at the Edge couple with 5G to become more mainstream. Some specific applications that will benefit from this technology include autonomous driving, robotic surgery, unmanned aerial vehicles, 5G base stations, and automated drilling control.

(As shown in the diagram, the pin-out that’s specified for the COM-HPC server module accommodates for an abundance of high-speed I/O.)

The new connector that’s specified for COM-HPC can handle the higher speeds associated with PCIe Gen 5, which checks in at 32 GTs/s. And the connector’s 400 pins allow for more signals than ever before. With the 5-mm height of the connector, there’s enough space to place most of your ICs. A closer look at the signals coming through that connector show a single 12-V input with 5% margin. There’s also a lot of flexibility in how you handle the PCIe signals (see the figure).

More Memory, Too

“In terms of memory, with the eight DIMM slots, using 32-Gbyte modules, the current sweet spot for memory, you can go up to 256 Gbytes with COM-HPC,” says Henk van Bremen, director of embedded boards and modules for ADLINK Technology. “You can go higher if your application requires it. Or if you deploy lower capacity DIMMs, you can cost reduce your system.”

Great Minds Came Together

As in the development of many industry specifications, the COM-HPC spec required a very close cooperation between competitors. The result is the best case for both module manufacturers and module users. Note that, thanks to some great forethought, the modules can be deployed in harsh environments. If water colling is necessary, that would not be an obstacle.

To learn more ab out the server side of the COM-HPC spec, check out the video featuring ADLINK’s van Bremen.