# Asrock Q1900M Pro3 random hangs and unable to reboot

## ktsaou

Hi all,

I recently started swapping my gentoo routers/PBXs with J1900 machines consuming a lot less power compared with normal PCs.

I require a plain old PCI slot to install my digium cards for asterisk.

The first machine I got was a Gigabyte J1900N-D3V, which is running without any issues.

Now, I got an Asrock Q1900M Pro3 (it gets normal DIMMs instead of S0 DIMMs and it has more PCI/PCIe slots).

Apart the above, the two machines are very close in specs.

However, the Asrock Q1900M Pro3 has 2 problems:

 it does not reboot.

Linux shuts down and requests a reboot, but the machine either freezes at BIOS or shortly after linux boots again (at the CPU detection).

 it randomly hangs.

Both machines run the same gentoo installation (I just rsynced the files from the Gigabyte to the Asrock).

However the Asrock hangs after a few days mostly during the night (I guess a cron job triggers this).

There is no kernel panic. It just freezes.

I tried kernels 3.14.14-gentoo and 3.16.5-gentoo.

Both have the same issue.

I installed Windows 8.1 to check if the issues appear there too. They are not. Windows 8.1 is stable and is perfectly capable of rebooting the machine over and over again.

So, I guess there is something linux does, that the Asrock BIOS/motherboard does not like.

Any ideas where to look?

PS: I already did a memcheck on the Asrock. It is good.

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## eccerr0r

I'd probably get an RMA the motherboard, if you know your power supply is good (trade PSUs on your machines?)

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## ktsaou

Hi,

Thanks for replying..

Since Windows 8.1 runs perfectly on this machine, I don't think there is a h/w problem.

It is probably A BIOS problem... or something related to Linux (old-fashioned way of) booting and this new line of BIOSes that have been tested under Windows but not under Linux.

I am not an expert, but I don't see a h/w problem (and their service team will not find one either)...

Thanks!

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## eccerr0r

Well you have two software setups that are identical and one fails...

If it's not hardware then it's firmware, so unless you can get new firmware, I'd still suggest hardware problem.  Every time I have a machine that randomly freezes it ended up being a motherboard or power problem...

Best you can try is disabling ACPI and seeing if it still freezes but you'll lose a lot of functionality.  If it still freezes with ACPI disabled, definitely RMA the board.

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## krinn

What you should just do is download a livecd from a random linux distro (but avoid a Gentoo, you may just favor what is the most popular linux distro currently, i'm not sure who own the crown now).

If it works : that's your config issue and it should be fix with some kernel change.

If it still doesn't work :

-If you brought the m/b with some kind of sticker on it "only for windows 8" you have no reason to complain.

-If the m/b doesn't mention it is exclusive to windows 8 ; it is then a failure from the board. Whatever it is bios or design, it has a flaw and it's upto them to fix it.

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## ktsaou

I installed arch linux on excactly the same hardware (even the same disks).

The problems seem to be solved (it can reboot without issues and it is stable so far).

I got the kernel config from arch and build the same kernel myself.

Problems appear again under gentoo.

I noticed that under gentoo the genkernel generated initramfs loads all available disk drivers when it boots. Arch does not, it just loads the drivers it needs - not everything.

So I guess there is a not-needed kernel module or driver that genkernel is loading, which corrupts something in BIOS.

Is there a way to instruct genkernel to load only the disk drivers needed by the system it runs?

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## ktsaou

Just for completeness to add that on Arch, Asrock Q1900M Pro3 is stable, but like Gentoo, it cannot reboot the machine. Sometimes it works, but most of time it just hangs at the BIOS screen.

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## ktsaou

After several months of frustration, I found that this motherboard (and possibly other Asrock baytrail-d motherboards) need these kernel options:

```
reboot=pci

intel_idle.max_cstate=1

```

The first one fixes the reboot issue.

The second one disables processor cstates above 1. This is the reason for the lockups. The processor cstates can be configured from BIOS too.

The above are needed even with latest BIOS (1.20 currently) and latest kernels (tried up to 4.2.5).

References:

https://bugs.freedesktop.org/show_bug.cgi?id=88012#c117

https://bugzilla.kernel.org/show_bug.cgi?id=109051

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