Frequently Asked Questions


Drivers & Software


  • How much power does this CPU board need?

    This is a difficult question to answer accurately. ADL Embedded Solutions offers a wide range of CPU boards; from low power 1.1GHz Atom™ processors (which can operate on as little as 7Watts of power, all the way up to a 2.1GHz Quad-Core i7 (which can require more than 50W of power under full load).

    Total power consumption will also depend on the memory and I/O devices installed, the operating temperature of the board, and how much processing power is required from the main CPU during full load. Newer PC/104 board designs like the ADLGS45PC, ADLD25PC and the ADLQM67PC contain full support for ACPI power scheme. ACPI support is similar to the power features found in modern laptops. It allows the OS to monitor processor demand and input from the user, and control hardware and processor clock speeds in order to conserve power.

    The easiest way to compare processor boards is to find the Intel Thermal Design Power (TDP) values for each processor. TDP Values for all Intel Processors are available in Intel’s support website. Although the TDP value for a processor does not represent the maximum power consumption, it is a clearly defined upper limit for the thermal maximum (and therefore closely related to total power consumption) of the CPU. Assuming the I/O and memory are the same for both systems, customers can compare the TDP values for each processor to get a simple relative measure of the power consumption under “real-world” situations.

  • How much does the board and cooling solution weigh?

    Most of our bare CPU boards have a mass of approximately 100 grams including the DDR-RAM memory module. The total mass of the CPU board will depend on the cooling solution and connectors installed (some of our larger cooling solutions can weigh twice as much as the board).

  • Can I run my CPU without a cooling fan? (Passive cooling only)

    Lower power CPU boards such as the ADLLX8PC, ADLS15PC, and ADLN2000PC can safely operate in office, lab or warehouse environments (0° to +70°C) using only a passive cooling solution (a finned heatsink with no fan). Passive cooling solutions sold by ADL Embedded Solutions are not recommended for Extended Temperature Environments above +70°C.

    High performance CPUs (ADLQM67PC, ADLGS45PC) must use active cooling (either an installed CPU fan or an external fan that forces air over the heat sink).

    CPU boards with heat-spreaders should not be run on the benchtop without some way to dissipate the heat away from the processor. Several of our heat-spreaders can be purchased with an optional heatsink that quickly bolts onto the top of the solution to allow operation in the open air.

  • Do you offer a 66MHz CPU? / What’s the slowest CPU you offer?

    The ADLLX8PC uses an AMD LX8 Geode processor, which operates at a 500MHz clock frequency, but BIOS settings on this board allow the CPU frequency to be set as low as 300MHz. This option can also be hard-wired into the board as a special factory modification. Please contact your sales rep for details.

    Although we occasionally receive requests for CPUs with slower 66MHz clock speeds, many of these older processors are not supported by our chip vendors anymore, so as a result, we do not currently offer any 66MHz or 133MHz processors to replace these legacy PC/104 systems. ADL Embedded Solutions remains committed to helping developers create new designs using modern processors that are faster, more reliable, and use less power.

  • What’s the fastest CPU you offer?

    The ADLQM87PC-4700EQ is the fastest CPU board currently available in PC/104 small form factor. This board features an Intel i7 2.4GHz Quad Core Processor with 6MB of cache. This is the fastest PC/104 board on the market today; it’s been benchmarked atover 85GIPS !!

  • Are there any CPUs with a 25MHz PCI bus?

    The PCI bus rate is 33MHz on every board we sell…Except for 4 boards. The following 4 CPU boards have a clock rate of only 25MHz:

    p/n 29231x ADLS15PC-11x 1.1GHz atom Z510 CPU

    The 4 boards in the 31x product line use an Intel Z510 1.1 Ghz Atom processor, with a slightly slower 100MHz clock frequency to achieve the ultra-low power consumption. On these boards, the PCI bus is set to run 25MHz (a simple 4x divider from the main clock frequency).

    Although 33MHz PCI buses are now standard across the industry,most OS and device drivers are tolerant of the slower 25MHz PCI clock. Although running the PCI bus at 25MHz does help lower the overall system power requirements, some RTOS and customized software may be affected.

    If you must have the 33MHz PCI bus speed for your legacy code and I/O, you can simply upgrade to the 1.6GHz processor (exact same board but it uses the Intel Z530 1.6Ghz processor instead).

    The following 4 boards are identical to those listed above, except they have the faster 1.6GHz CPU and a faster (33MHz) PCI bus.

    p/n 29236x ADLS15PC-16x 1.6GHz atom Z530 CPU


  • How many boards can I fit into a single stack?

    The PC/104 specification allows for up to 4 I/O boards in a single stack. PCI-to-PCI bridge cards can be installed to allow the addition of extra ISA or PCI boards. The total number of I/O cards will ultimately be determined by the current consumption and I/O bandwidth for all the cards combined. Please contact your sales rep for additional information on the limitations for specific boards and system busses.

  • What’s the difference between a Heat Sink and a Heat Spreader?

    A heat sink is a traditional cooling solution that maximizes the surface area (using fins or pins) and airflow (using fans) to dissipate heat from the processor out into the surrounding air. Heat sinks with built in cooling fans are a simple, lightweight, and completely self-contained cooling solution. Depending on the available airflow they can often out-perform a similar sized heat-spreader.

    Heat spreaders have a large, flat surface on top. They have no fan and no fins. Instead of cooling by forced air, the spreader is pressed directly up against another large flat surface (for example: the frame of a vehicle or the inside wall of a sealed container) and heat is allowed to pass from the small heat spreader out to the larger metal surface. Heat spreaders do not cool the CPU by themselves, they only transfer the heat to another object where it can safely dissipate away from the processor. Heat spreaders are ideal for systems that expect to operate under extreme shock and vibration, or systems that need to be completely sealed inside a container to protect it from the environment.

    Fig 1) Identical CPU boards using a heatsink (left) and heat spreader (right).

  • What is the expected life of the CMOS Battery?

    ADL Embedded Solutions CMOS batteries (p/n 100-9655) are based on a 3.6V Lithium Thionyl Chloride battery, with a 100k ohm, 5%, ¼W, current limiting resistor installed to protect battery life. The resistor provides a voltage drop for a 10uA or smaller load so that the 3.6V potential does not produce excessive on-state current. Current does flow from the battery in the ON state. It is significantly less with the resistor. If no resistor was used, damage to the circuitry could occur, and the battery drain in the ON state would exceed that in the OFF state.

    Most modern chipsets can keep the RTC running with less than 10uA of current from the battery, with 6uA being a typical requirement. Using the 1.20Ah rating of the battery, the life expectancy would be 1.2A/6uA = 200,000 hours, or about 22 years at +20°C. Considering that the self-discharge of the battery is <1% per year at +20°C, it is reasonable to expect that the useful life of the battery is indeed, >10 years. For serviceable applications, we suggest a 5 year service interval, in general. Regardless of the ideal time interval or operating conditions, CMOS batteries sold by ADL Embedded Solutions are mass produced and not rechargeable. ADL Embedded Solutions recommends that all developers include connectors and/or clips in their system design so that their CMOS battery can be easily replaced in the field.

  • How do I implement the LAN activity LED on the ADLGS45PC?

    The LED configuration for the GS45 LAN ports are based on the diagrams in the Intel 82579 User’s manual. (see the link below). The reference diagram is on page 239 of this manual.

    There is a 300-ohm current limiting resistor in the reference diagram. The ADLGS45PC has a built-in 330-ohm resistor for both the SPEED100 and LINKACT signal lines. For those 2 LAN indicators, it’s possible to just wire in the appropriate LED to the signal pin at one end, and the other end to the 3.3V power at pin12 and you’re done.

    The SPEED1000 LED (pin 7) does NOT have the 330-ohm inline resistor, and this is different from the other two signals (I’m not sure why). If you plan on using that LAN LED, you may need to add one in your design.

  • It’s not booting! What should I do?
  • My ADL Embedded Solutions SBC will not boot up. When I turn it on there is no display or keyboard, but I can see a flashing YELLOW LED on the board. What could be the problem?

    The ADL Embedded Solutions SBC’s ADLS15PC, ADLGS45PC, ADLD25PC, ADL2000PC, ADLQM67PC, ADLQM87PC, and ADLE3800PC, employ a power management PIC that monitors and controls the gating of supply power into the SBC. This Power Management PIC includes a status LED that can provide some indication as to the condition of the system power as it pertains to the SBC. The following colors / conditions are defined for specific (and non-specific) board states. The following table describes some of the status LED states:

    Status Codes RGB LED:

    Color Interval Meaning
    none solid Invalid system state
    White solid The microcontroller has just been flashed and is being prepared for normal operation after reboot
    Cyan solid Reserved
    Magenta solid Reserved
    Blue solid Reserved
    Yellow solid Reserved
    Green solid Board operates normal
    Red solid Board is in Reset
    Green/Yellow flashing Bootloader operates normal
    Red flashing Firmware is being started (start sequence still running)
    Red/Yellow flashing Bootloader is being started (start sequence still running)
    Red/Magenta flashing Checksum error during I2C transmission in bootloader
    Red/Blue flashing Update completed, waiting for manual Reset
    Yellow flashing (10s) S5 state
    Yellow flashing (6s) S4 state
    Yellow flashing (3s) Reserved
    Yellow flashing (0.5s) Reserved

    There may also be variations that are not covered by the table above.

    In most cases, any RED LED means that there is an issue with the supply power. The status LED turns RED when the PIC is in RESET.

    Reset is caused by the following:

    • Source power has been asserted: PIC will go into reset at first power up to keep unstable power from entering the SBC. Once stable power it detected, it will gate the supply power into the board to allow it to boot.
    • Flashing red: Power has been asserted and the Status LED flashes Red. There is an undervoltage/undercurrent condition that is perhaps caused by an undersized power supply, undersized wire gauge or not all supply power pins are being used.
    • Solid Red: Overvoltage / Overcurrent or catastrophic error in the PIC, possibly due to an abnormal power event.


    A yellow LED typically indicates standby or sleep states, however there are also undefined states not covered by the table above. These types of conditions can be caused by abnormal power events can happen infrequently. For the defined YELLOW states above, using the board momentary switch will return the board to normal operation. For the reserved states, or other undefined YELLOW LED conditions, it may be necessary to remove all power from the SBC including the CMOS battery, to clear out any erroneous data inside the PIC.

    For any occurrence not described please contact ADL Embedded Solutions Technical Support for more in-depth troubleshooting.

  • How can I reset the Video monitor in the BIOS? (blind BIOS reset).

    The most common reason video monitors go blank is because users change video settings in the BIOS before they understand how it changes the Video output.

    • VGA Monitors must be plugged in before the system boots. The VGA monitors are detected like any other plug-and-play device, so if the BIOS does not detect the monitor during the first strart up, the BIOS may skip over it and set another video output as the “default” video display.
    • For a stock BIOS, the default video display will always be VGA. Always confirm the VGA video output is properly connected and working before you change any video settings in the BIOS.
    • When setting up an LCD or LVDS we recommend setting BIOS outputs to ”dual” or “clone” mode, and work with two monitor outputs. Don’t disable the VGA output until you are sure both displays are working properly.
    • Before changing any Video BIOS settings; Write down the keystrokes you need to enter the bios, “load default values >> save and exit”


    For example:

    On the ADLQM67PC:

    F7 (enters bios)

    >> F5>>F6>>’Enter’>>’Y’>>’Enter’

    (system should reboot at this point with VGA output enabled)

    On the ADLS15PC: Delete (enters bios)

    >> right arrow>> right arrow>> right arrow

    >> down arrow>> down arrow >> ‘Y’>> ‘Enter’ >> “Enter”>>”y””>>’Enter’

    (system should reboot at this point with VGA output enabled)

  • I need to update the BIOS. How do I do that?

Power Supply

  • hat is the difference between AT and ATX power supplies?

    AT power scheme is the original power scheme that most of the older computers used. AT-style computer cases had a power button that is directly connected to the system computer power supply. Pushing the power button kills all the power instantly (whether the Operating System is ready for it or not!)

    An ATX power supply is typically controlled by an electronic switch. Instead of a hard switch at the main power input, the power button on an ATX system is a sensor input monitored by the computer. ATX systems allow the Operating System to control the final “off” signal to the power supply; this gives the OS time to save all information and complete important tasks before turning off the power supply using a dedicated output signal (PS_ON#). ATX power supplies also support lower power modes. They have an additional “Standby” power output (5VSB) that stays on to power standby devices whenever the system goes into low-power mode.

    The ATX specification is the newer and more power efficient design. It is superior to the AT power supply scheme, and is used on almost all modern desktop and laptop computers. ADL Embedded Solutions offers PC/104 power supplies that support the ATX power scheme with 5V, 12V and 5VSB outputs only. Although the full ATX specification has additional voltages (12V, -5V and 3.3V), these extra power inputs are intended for Desktop systems; most embedded systems have no use for these extra voltage inputs and so they are omitted to save power and space.

  • Can I run my CPU on just a single 5-Volt Supply?

    Yes, but some systems may require a hardware modification to accomplish this. Please refer to the chart below or contact your Sales rep for additional information:

    CPU Board Power Voltages Required
    ADLLX8PC AT 5 volt only (12V input optional)
    ADLS15PC AT 5 volt only (12V input optional)
    ADLD25PC ATX 5 volt only (12V input optional)
    ADLN2000PC ATX 5 volt only (12V input optional)
    ADL855PC AT 5 volt only (12V input optional)
    ADL945PC AT 5 volt only (12V input optional)
    ADLGS45PC ATX 5V + 12V** (**requires minor hardware mod for 5V only operation)
    ADLQM67PC ATX 5V + 12V** (**requires minor hardware mod for 5V only operation)
    ADLQM87PC ATX 5V + 12V** (**requires minor hardware mod for 5V only operation)
    ADLE3800PC ATX 5 volt only (12V input optional)


  • How do I shut off the power supply on the ADL855PC or ADL945PC?

    The ADL945PC does not have an independent Suspend power input, so it cannot fully support the ATX power scheme without external hardware. For customer that require an ATX-style power shutoff, ADL Embedded Solutions has an app note (Power Switch Implementation) that describes how to build this circuit. Note, the app note is only a starting point for customer designs. ADL Embedded Solutions does not sell an adapter board with this circuitry, and cannot assist users in the building or debugging this circuit.

  • Why doesn’t the power button work on the ADL855PC or ADLS15PC?

    Although the power button input can be used to shut-down the computer, a complete shutdown of the system is not possible without an ATX style power supply and full ACPI support in the CPU board. The power button can signal the Operating System to initiate a software shut-down, but there is no way to turn off the main power (no PS_ON# output).

Technical Support

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Customer Service

Should our product require repair, our Customer Service department provides prompt service. Warranty repairs are performed without charge. Products out of warranty are repaired at very moderate prices. Contact Customer Service >


Product data sheets and manuals, as well as drivers, diagrams and other technical information can be found in the downloads section. View Downloads >