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apu3a4 System board
Status active
Part numbers apu3c2 = 3 i211AT LAN / AMD GX-412TC CPU / 2 GB DRAM
apu3c4 = 3 i211AT LAN / AMD GX-412TC CPU / 4 GB DRAM
apu3b2 = 3 i211AT LAN / AMD GX-412TC CPU / 2 GB DRAM
apu3b4 = 3 i211AT LAN / AMD GX-412TC CPU / 4 GB DRAM (superseded)
apu3a2 = 3 i211AT LAN / AMD GX-412TC CPU / 2 GB DRAM (superseded)
apu3a4 = 3 i211AT LAN / AMD GX-412TC CPU / 4 GB DRAM (superseded)
Application This board version is targeted at applications that require 2 3G / LTE modems. SIM sockets can be swapped under GPIO control, enabling failover between two different networks even when only one modem is used. Another feature is the build option for a regular PCI express slot on the side.
Use with case1d2u / case1d2blku / case1d2redu / case1d2bluu enclosures
ac12veur3 / ac12vus2 / ac12vuk AC adapter
msata16f / msata16g mSATA SSD
sd4b SD card
wle200nx / wle600vx miniPCI express wireless modules
spi1a flash recovery module
  • CPU: AMD Embedded G series GX-412TC, 1 GHz quad Jaguar core with 64 bit and AES-NI support, 32K data + 32K instruction cache per core, shared 2MB L2 cache.
  • DRAM: 2 or 4 GB DDR3-1333 DRAM
  • Storage: Boot from SD card (internal sdhci controller), external USB or m-SATA SSD. 1 SATA + power connector. mSATA is shared with miniPCI express.
  • 12V DC, about 6 to 12W depending on CPU load. Jack = 2.5 mm, center positive
  • Connectivity: 3 Gigabit Ethernet channels (Intel i211AT)
  • I/O: DB9 serial port, 2 USB 3.0 external + 4 USB 2.0 internal, three front panel LEDs, pushbutton
  • Expansion: 3 miniPCI express (J14 USB or mSATA, with SIM; J15 USB only, with SIM; J16: full miniPCI express, but no SIM, intended for wifi). GPIO header, optional I2C bus, COM2 (3.3V RXD / TXD).
  • Board size: 6 x 6" (152.4 x 152.4 mm) - same as apu1d, alix2d13 and wrap1e.
  • Firmware: coreboot (please contact support@pcengines.ch for source code if desired).
  • Cooling: Conductive cooling from the CPU to the enclosure using a 3 mm alu heat spreader (included).
OEM options PCI express slot on the side, different number of LAN ports, etc.
Documentation user's manual
Howto HowTo collection
Cooling assembly apu cooling assembly instructions
Version apu3c:
  • Improve compatibility with LTE modem modules: Disconnect SMB_DAT / SMB_CLK signals (1.8V level on Quectel).
  • Improve compatibility with LTE modem modules: No stuff diodes D4 / D17, option resistor bypass (extremely low VIL on Huawei modems, sensitive to incoming EMI).
  • Optional SIM presence indicator / SIM card detect.
  • Disable non-functional NCT5104D watchdog timer.
  • Increase 3.3V current limit to allow for two simultaneous LTE modems.
  • Some DFM changes.
Version apu3b: Fixed USB header J13 pinout.
Version apu3a: The pinout on USB header J13 is wrong, do not use.
BIOS update Please see Howto collection for instructions on BIOS upgrade.

Update 3/2017: various fixes, enable additional USB ports, iPXE with setup, set SIM switch GPIO to high.

Schematic apu3a / apu3b / apu3c schematics,
Manufacturer PC Engines
Origin Taiwan
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