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Whenever I wake my computer out of suspension, I get the following error code.

[Firmware Bug]: cpu 1, try to use APIC500 (LUT offset 0) for vector 0x400, but the register is already in use for vector 0xf9 on another cpu

Before the part that says [Firmware Bug] is a list of numbers. They always change, but I'll put in an example.


My CPU is an AMD Athlon II X3, if that helps. Any ideas?

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Not just a Ubuntu issue; a long-standing Linux kernel issue. The bug report lists kernel 3.5.0, and I'm running kernel 4.1.27. – palswim 2 days ago

It's a BIOS bug common on AMD platforms. The above bug report thread explains it in fairly exhaustive detail. It doesn't seem to be a serious concern. I have an AMD Phenom II and I get the same error message. Seems like developers are trying to come up with a kernel patch that might help avoid this issue, but ultimately, it's a problem of the way the BIOS interacts with the processor when the computer wakes from suspend.

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It doesn't seem like a serious concern for certain older processors ("10h"), but it appears to cause system slowness for a newer family of processors ("15h"). – palswim 2 days ago

I had the same problem with my toshiba with AMD A8-5545M APU.

BIOS update before installing Linux from Windows is the learning curve.

There is a work around but its a mess..

check your OEM BIOS updates.

NOTE: Flash your BIOS at your own risk.

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