Scope
This document explains how to modify an Omnia.7 Supermicro motherboard that won't boot. This mod may allow the motherboard to be revived and boot normally again.
Description
This modification addresses a weakness in the Intel Atom processor used in SupermIcro A1SRI 2758F motherboards, where the LPC clock stops functioning, preventing the motherboard from booting (the LPC is a PCI-ISA bridge controller). The workaround uses a 220-ohm resistor to pull the LPC pin to 3.3V, removing LPC dependencies from the boot sequence. While this fix affects the ability of the board's IPMI to talk to the operating system, Omnia.7 does not use this function, so it is of no concern.
Procedure
This mod consists of simply adding a 220 Ohm resistor between Pins 1 and 9 on the bottom of the board header, as shown in the photo below. This fix as has revived several Omnia 7 motherboards in our service center that have a "Blue power light ON, but the screen says NO SYNC" symptom.
With the 220 Ohm resistor in place, as shown below, this main board may boot properly again:
While you can access these pins from the top of the board (possibly building a plug to fit in the connector), we recommend using this approach only for verifying the fix or for short-term field use since this may interfere with SATA connections and is less robust.
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