First lets return the kernel and inits back to the way they were installed by FOG. You can upgrade the kernel to the latest, but the inits need to be what was installed by FOG.
Second, lets try a kernel parameter of
acpi=off. If this system hasn’t been registered yet, you can set this in the global parameters under FOG Settings->FOG Configuration page. Just be aware this is a global parameter and will apply to all hosts when they are pxe booted. If the host has been registered, then you can go to the host definition and set the kernel parameters there, then it will only apply to this host.
I don’t know if this is a fix for your case, but we’ve been tracking the CPU stall messages and this has fixed the issue on other hardware.