Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[Fox Steward]

Dear Peter and all,

I could find a fix/hack for the BIOS boot problem as described.

I did not manage to file a bug report for it yet though.

After successfully installing I now have more problems such as

- zzz (suspend) and (hibernate) not working (see bug report [1])
- function keys for screen brightness not working 

@Peter: did these things work for you?

It seems the reason for all this trouble is a broken/outdated BIOS.

I wonder if Clevo - the manufacturer - would be eager to bring some fixes.

And of course, in the long run, we need a "free" BIOS for everyone. ;-)

Sincerely,

Fox


[1] https://marc.info/?t=15535409473&r=1&w=2

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[finkfox]

Hi again.

Just a quick update.

After adding some "bogus" partitions 0 to 2 in front of openbsd paritition 3 
the BIOS no longer hangs with disklabel data. I can now install, boot and run 
OpenBSD from SSD on SATA.


$ doas fdisk sd0

Disk: sd0   geometry: 31130/255/63 [500118192 Sectors]
Offset: 0   Signature: 0xAA55
Starting Ending LBA Info:
 #: id  C   H   S -  C   H   S [   start:size ]
---
 0: EE  0   0   2 -  0   0  11 [   1:  10 ] EFI GPT 
 1: 05  0   0  12 -  0   0  32 [  11:  21 ] Extended DOS
 2: 83  0   0  23 -  0   0  54 [  22:  32 ] Linux files*
*3: A6  0   1   2 -  31129 254  63 [  64:   500103386 ] OpenBSD



I tried this with the intuition that this might stop the BIOS from "seeing" the 
disklabel data. And fortunately it worked. To really understand what is going 
on I guess one would need access to the BIOS source code, or? 

Should this issue be reported as an "official" bug?

At least other Clevo W840SU laptop users could benefit from this knowledge.

Best regards,

Fox

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[finkfox]

Hello again.

Thank you Peter for your feedback and describing the steps that 
seem to have solved your problems so long time ago.

To be hontest, at this point in time I feel a bit reluctant to test
with two disks attached mSATA and SATA, I would rather focus
just on one disk attached via SATA.

For that purpose I have now executed a bit more debugging work.

>From this work I conclude: the BIOS hang up is introduced by the writing
of disklabel data. The disklabel data that remains, after all disklabel
partitions where removed (in disklabel editor command z).

Further below you can find a detailed log with hex dumps which which gives
reason for this claim.

Questions:

Does anyone have an idea what could be the problem with this disklabel data?

Why does the BIOS even care about this data and at this point of time in the 
first place?
Especially since I did not complete a OpenBSD install, there is no Partition 
Boot Record / stage 1
bootloader in place yet the BIOS could trigger.

Any help for this issue is greatly welcome.

Thank you very much.

Fox


== LOG START ==

Given:

1. SSD connected via SATA port (no mSATA connected) on Clevo W840SU laptop

Steps:

0. Connect SSD disk to other openbsd system/laptop 

With OpenBSD -current via USB adapter here it appears as sd2 device.

1. Remove any data from first 2M of disk: 

$ doas dd if=/dev/zero of=/dev/sd2rc bs=2M count=1 

2. Initialize MBR: 

$ doas fdisk -iy sd2

3. Check: attach disk to Clevo laptop at SATA port 

=> Bios does not(!) hang upon boot, Bios boot works!

4. Re-attach disk to other laptop via usb adapter

5. Write disklabel: 

$ doas disklabel -E sd2 

In the editor menu: A; q

6. Extract disklabel data

Which is written to the first 512 Bytes after the partion boot record (PBR).
The PBR is written in the first 512 Byte of the OpenBSD partition,
With the default fdisk MBR layout the PBR is written to sector 64.

$ doas dd if=/dev/rsd2c of=/home/user/debug skip=65 bs=512 count=1
$ hexdump -C /home/user/debug

 57 45 56 82 04 00 00 00 53 43 53 49 20 64 69 73 |WEV.SCSI dis|
0010 6b 00 00 00 00 00 00 00 53 53 44 20 38 34 30 20 |k...SSD 840 |
0020 50 52 4f 20 53 65 72 69 00 02 00 00 3f 00 00 00 |PRO Seri?...|
0030 ff 00 00 00 9a 79 00 00 c1 3e 00 00 b0 32 cf 1d |.y...>...2..|
0040 76 bc fc 2c 21 23 84 61 00 00 00 00 00 00 00 00 |v..,!#.a|
0050 40 00 00 00 1a f9 ce 1d 00 00 00 00 00 00 00 00 |@...|
0060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ||
0070 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ||
0080 00 00 00 00 57 45 56 82 ce a5 10 00 00 20 00 00 |WEV.. ..|
0090 00 00 01 00 00 00 20 00 40 00 00 00 00 00 00 00 |.. .@...|
00a0 07 14 01 00 30 59 ff 00 40 00 20 00 00 00 00 00 |0Y..@. .|
00b0 01 00 00 00 b0 32 cf 1d 00 00 00 00 00 00 00 00 |.2..|
00c0 00 00 00 00 e0 ff 7f 00 80 59 1f 01 00 00 00 00 |.Y..|
00d0 07 14 01 00 60 b2 6e 02 60 59 9f 01 00 00 00 00 |`.n.`Y..|
00e0 07 14 01 00 00 00 40 00 c0 0b 0e 04 00 00 00 00 |..@.|
00f0 07 14 01 00 00 00 20 00 c0 0b 4e 04 00 00 00 00 |.. ...N.|
0100 07 14 01 00 00 00 80 02 c0 0b 6e 04 00 00 00 00 |..n.|
0110 07 14 01 00 00 00 40 00 c0 0b ee 06 00 00 00 00 |..@.|
0120 07 14 01 00 00 00 c0 00 c0 0b 2e 07 00 00 00 00 ||
0130 07 14 01 00 40 ed e0 15 c0 0b ee 07 00 00 00 00 |@...|
0140 07 1c 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ||
0150 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ||

7. Check: attach disk to Clevo laptop at SATA port

=> Bios hangs at boot.

8. Re-attach disk to other laptop via usb adapter

9. Remove disklabel partitions: 

$ doas disklabel -E sd2

In the editor menu: z

10. Extract disklabel data (compare step 6)

$ doas dd if=/dev/rsd2c of=/home/user/debug2 skip=65 bs=512 count=1
$ hexdump -C /home/user/debug2

 57 45 56 82 04 00 00 00 53 43 53 49 20 64 69 73 |WEV.SCSI dis|
0010 6b 00 00 00 00 00 00 00 53 53 44 20 38 34 30 20 |k...SSD 840 |
0020 50 52 4f 20 53 65 72 69 00 02 00 00 3f 00 00 00 |PRO Seri?...|
0030 ff 00 00 00 9a 79 00 00 c1 3e 00 00 b0 32 cf 1d |.y...>...2..|
0040 76 bc fc 2c 21 23 84 61 00 00 00 00 00 00 00 00 |v..,!#.a|
0050 40 00 00 00 1a f9 ce 1d 00 00 00 00 00 00 00 00 |@...|
0060 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ||
0070 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ||
0080 00 00 00 00 57 45 56 82 36 4b 10 00 00 20 00 00 |WEV.6K... ..|
0090 00 00 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ||
00a0 00 14 01 00 00 00 00 00 00 00 00 00 00 00 00 00 ||
00b0 00 00 00 00 b0 32 cf 1d 00 00 00 00 00 00 00 00 |.2..|
00c0 00 00 00 00 00 00 00 00 00 00 00 00 00 0

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[Peter Nicolai Mathias Hansteen]

> 22. mar. 2019 kl. 07:16 skrev Peter Nicolai Mathias Hansteen 
> :
>> Dear Peter, can you remember more details how you got OpenBSD to work on that
>> Clevo W840-SU by any chance? Did you use SSD or HDD for the booting disk?
> 
> I considered it fairly obvious that I wanted the fastest one (the SSD) for 
> the system disk. I did not make any special preparations for that one (which 
> means the MBR would be intact), but it is entirely possible that I went for 
> the old-style (non-UEFI) option. The MBR removal was on the slightly roomier 
> HDD which I intended to use for /home.
> 

I should perhaps add to that, I was a little quick in typing up the previous 
answer.

If I remember correctly, I chose the old-style (not «secure boot») BIOS 
options, did a fairly regular install at first, but ran into something very 
much like the symptoms you describe. My conclusion then was that for whatever 
reason the system was trying to boot from the HDD (which then had an MBR but 
nothing else required for a boot disk), not the SSD.

After quite a bit of mucking about with options I never documented properly, as 
I remember it what gave me a functional system with the SSD as the system disk 
and I think something very close to the OpenBSD installer’s default 
partitioning plus the roomier HDD (later replaced with a same-size SSD but 
that@s another story) involved removing the MBR on the HDD. Then again, this 
was several years ago so and I did not make any notes that have survived while 
I was doing this. As you have seen already, you will need an MBR on the disk 
you intend to boot from.

- Peter

—
Peter N. M. Hansteen, member of the first RFC 1149 implementation team
http://bsdly.blogspot.com/ http://www.bsdly.net/ http://www.nuug.no/
"Remember to set the evil bit on all malicious network traffic"
delilah spamd[29949]: 85.152.224.147: disconnected after 42673 seconds.






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Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[Peter Nicolai Mathias Hansteen]

> 21. mar. 2019 kl. 22:55 skrev fink...@dismail.de:
> 
> Dear Peter and all.
> 
> Unfortunately I celebrated to early it seems. :-/
> 
> In my last post I described a hack in which I let the OpenBSD partition
> start at "sector 0" in order to avoid BIOS hangup.
> 
> When I now tried this way of setup with a SSD disk instead of HDD,
> after a succesful install, OpenBSD boots with the following Kernel panic:
> 
> "openbsd panic root filesystem has size 0"
> 
> For this I found the following post talking about "partition offset" [1].
> 
> It explains:
> 
> "Sector 0 can't be used for a partition, because it's occupied by the MBR 
> partition table"
> 
> So I believe the "Sector 0" hack is actually breaking things (as the fdisk 
> output
> of the result parition table also suggests).
> 
> Dear Peter, can you remember more details how you got OpenBSD to work on that
> Clevo W840-SU by any chance? Did you use SSD or HDD for the booting disk?

I considered it fairly obvious that I wanted the fastest one (the SSD) for the 
system disk. I did not make any special preparations for that one (which means 
the MBR would be intact), but it is entirely possible that I went for the 
old-style (non-UEFI) option. The MBR removal was on the slightly roomier HDD 
which I intended to use for /home.

- Peter
—
Peter N. M. Hansteen, member of the first RFC 1149 implementation team
http://bsdly.blogspot.com/ http://www.bsdly.net/ http://www.nuug.no/
"Remember to set the evil bit on all malicious network traffic"
delilah spamd[29949]: 85.152.224.147: disconnected after 42673 seconds.






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Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[finkfox]

Dear Peter and all.

Unfortunately I celebrated to early it seems. :-/

In my last post I described a hack in which I let the OpenBSD partition
start at "sector 0" in order to avoid BIOS hangup.

When I now tried this way of setup with a SSD disk instead of HDD,
after a succesful install, OpenBSD boots with the following Kernel panic:

"openbsd panic root filesystem has size 0"

For this I found the following post talking about "partition offset" [1].

It explains:

"Sector 0 can't be used for a partition, because it's occupied by the MBR 
partition table"

So I believe the "Sector 0" hack is actually breaking things (as the fdisk 
output 
of the result parition table also suggests).

Dear Peter, can you remember more details how you got OpenBSD to work on that
Clevo W840-SU by any chance? Did you use SSD or HDD for the booting disk?

> March 20, 2019 8:46 AM, "Peter N. M. Hansteen"  wrote:

> "I *think* what I did back then was set the all parts to size zero, except 
> the OpenBSD part which I set to the largest > the program would let me."

What were the other parts (partitions)?

Any further ideas and hints what I could try?

Thank you very much.

Fox

---
[1] https://unix.stackexchange.com/questions/148589/partition-offset-at-63-or-64

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[finkfox]

Dear Peter and all,

> I believe both should be doable using openbsd's fdisk (available I think from 
> the bsd.rd
> installer image), try escaping to the shell from the installer, possibly 
> fdisk -e and
> keep the man page handy. I *think* what I did back then was set the all parts 
> to size
> zero, except the OpenBSD part which I set to the largest the program would 
> let me.

Thank you. With this hint of yours I managed to finally find a solution.

1. I noticed that after doing with OpenBSD "fdisk -e sdx; reinit mbr", booting 
disk form SATA (no mSata 
connected) would result in a BIOS hangup. 

Here is the fdisk output of that state:

Disk: sd2   geometry: 121601/255/63 [1953525168 Sectors]
Offset: 0   Signature: 0xAA55
Starting Ending LBA Info:
 #: id  C   H   S -  C   H   S [   start:size ]
---
 0: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
 1: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
 2: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
*3: A6  0   1   2 - 121600 254  63 [  64:  1953520001 ] OpenBSD

2. I then went back to the fdisk editor and changed the C/H/S size of the 
partition 3 Openbsd to the maximum values.

Disk: sd2   geometry: 121601/255/63 [1953525168 Sectors]
Offset: 0   Signature: 0xAA55
Starting Ending LBA Info:
 #: id  C   H   S -  C   H   S [   start:size ]
---
 0: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
 1: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
 2: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
*3: A6  0   0   1 - 121600 254  63 [   0:  1953520065 ] OpenBSD  

3. As a result, with this disk attached vis SATA, the BIOS would no longer hang

4. I then installed OpenBSD, choosding "OpenBSD" in the partitioning step

After this step the fdisk layout looks like this:

Disk: sd2   geometry: 121601/255/63 [1953525168 Sectors]
Offset: 0   Signature: 0xAA55
Starting Ending LBA Info:   


 #: id  C   H   S -  C   H   S [   start:size ]
---
 0: E8  15356  77   8 - 229721 118   4 [   246698998:  3443776305 ] 
 1: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
 2: 00  0   0   0 -  0   0   0 [   0:   0 ] unused  
 3: 00  0   0   0 -  0   0   0 [   0:   0 ] unused 

Isn't that a bit weird? The type ID is E8, Unknown?

5. On reboot, OpenBSD system boots and works fine. 

Now I don't really understand why this "hack" works.

Maybe someone has a valid explanation?

Lastly, this is just a first quick response, I haven't really tested the 
resulting
system, only logged in.

Thank you very much.

Fox

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[Peter N. M. Hansteen]

On Wed, Mar 20, 2019 at 08:17:51AM +, fink...@dismail.de wrote:
> In your blog post [1] you describe installing OpenBSD on your then (2017) new 
> silver colored laptop, a (Multicom) Clevo U831 with dmesg [2].
> 
> In the post you also mention your previous (2014) black colored laptop, a 
> Clevo W840SU with dmesg [3].
> This is the model I'm having trouble with.

Ah, I got that backwards, sorry. I claim a slight caffeine deficiency (soon to 
be corrected)

> Sepcifically you write:
> 
> "The main hurdle back when I was installing the 2014-vintage 14" model was 
> getting the system to consider the SSD which showed up as sd1 the automatic 
> choice for booting (I solved that by removing the MBR, setting the size of 
> the MBR on the hard drive that showed up as sd0 to 0 and enlarging the 
> OpenBSD part to fill the entire drive)."
> 
> It would be great to learn more details on these steps, that is
> 
> - how do I remove an MBR
> - how do I set the size of an MBR to 0
> 
> I believe these MBR tweaks might solve my hanging BIOS issue.

I believe both should be doable using openbsd's fdisk (available I think from 
the bsd.rd
installer image), try escaping to the shell from the installer, possibly fdisk 
-e and
keep the man page handy. I *think* what I did back then was set the all parts 
to size
zero, except the OpenBSD part which I set to the largest the program would let 
me.

- Peter

-- 
Peter N. M. Hansteen, member of the first RFC 1149 implementation team
http://bsdly.blogspot.com/ http://www.bsdly.net/ http://www.nuug.no/
"Remember to set the evil bit on all malicious network traffic"
delilah spamd[29949]: 85.152.224.147: disconnected after 42673 seconds.

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[finkfox]

Dear Peter,

thank you for your reply.

> Odd. I vaguely remember having to set the BIOS to look at the SSD (which 
> OpenBSD sees as sd1) but
> IIRC I only booted the machine from a USB drive once, for the initial install.
> 
> The only obvious points I see are that you’re pointing to the wrong dmesg 
> (the correct one is at
> https://home.nuug.no/~peter/20170927_dmesg_greyhame.txt) 

I'm sorry, I think I should have been more clear to avoid confusion.

Please correct me if I'm wrong:

In your blog post [1] you describe installing OpenBSD on your then (2017) new 
silver colored laptop, a (Multicom) Clevo U831 with dmesg [2].

In the post you also mention your previous (2014) black colored laptop, a Clevo 
W840SU with dmesg [3].
This is the model I'm having trouble with.

Sepcifically you write:

"The main hurdle back when I was installing the 2014-vintage 14" model was 
getting the system to consider the SSD which showed up as sd1 the automatic 
choice for booting (I solved that by removing the MBR, setting the size of the 
MBR on the hard drive that showed up as sd0 to 0 and enlarging the OpenBSD part 
to fill the entire drive)."

It would be great to learn more details on these steps, that is

- how do I remove an MBR
- how do I set the size of an MBR to 0

I believe these MBR tweaks might solve my hanging BIOS issue.

> I need to be off to work now, but I could perhaps compare more notes sometime 
> in the afternoon if
> needed.

That would great! Thank you very much!

Fox


[1] https://bsdly.blogspot.com/2017/07/openbsd-and-modern-laptop.html
[2] https://home.nuug.no/~peter/20170927_dmesg_greyhame.txt
[3] https://home.nuug.no/~peter/dmesg.elke.20170709.txt

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[Peter Nicolai Mathias Hansteen]

> 19. mar. 2019 kl. 20:59 skrev fink...@dismail.de:
> 
> I'm trying to run OpenBSD on a Clevo W840SU laptop. After a successful install
> and starting the machine the BIOS hangs. That is, when the booting drive is
> connected via SATA/mSATA. When connected via USB, it works just fine.

Odd. I vaguely remember having to set the BIOS to look at the SSD (which 
OpenBSD sees as sd1) but IIRC I only booted the machine from a USB drive once, 
for the initial install.

The only obvious points I see are that you’re pointing to the wrong dmesg (the 
correct one is at https://home.nuug.no/~peter/20170927_dmesg_greyhame.txt 
) and that I 
distinctly remember telling the installer to use the "W)hole disk» option on 
the SSD, with the UEFI options enabled — basically not changing anything from 
the default settings.

Off the top of my head I’d check that you’re actually telling the machine to 
boot off the drive that has the operating system installed. If you choose the 
wrong one, you would get behavior that matches (at least superficially) what 
you describe.

I need to be off to work now, but I could perhaps compare more notes sometime 
in the afternoon if needed.

- Peter

—
Peter N. M. Hansteen, member of the first RFC 1149 implementation team
http://bsdly.blogspot.com/ http://www.bsdly.net/ http://www.nuug.no/
"Remember to set the evil bit on all malicious network traffic"
delilah spamd[29949]: 85.152.224.147: disconnected after 42673 seconds.






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Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[finkfox]

> Is your BIOS set to RAID for the HDD? If so try setting it to AHCI in the 
> BIOS.

Nope, it is set to AHCI as the documentation attached to my original post 
describes.

Re: OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[tfrohw...@fastmail.com]

On March 19, 2019 7:59:49 PM UTC, fink...@dismail.de wrote:
>Dear Community.
> 
>   
>I'm trying to run OpenBSD on a Clevo W840SU laptop. After a successful
>install 
>and starting the machine the BIOS hangs. That is, when the booting
>drive is 
>connected via SATA/mSATA. When connected via USB, it works just fine.
>
>The identical laptop model is mentioned as a working one 
>in Peter Hansteen's blog (including a dmesg log) [1].  
>   
>
>A detailed documentation of the issue is given in the plain text
>document 
>attached. 
>   
>So is this a broken BIOS issue?
>What else could I try to get this to work?
>How to debug this issue further?   
>
>   
>I've been using GNU/Linux before and have had not problem with a
>hanging BIOS
>whatsoever. In fact it's still working without a problem on this
>machine.   
>  
>   
>Thank you very much for your attention and help.   
>   
>   
>Fox
>
>--
>[1] https://bsdly.blogspot.com/2017/07/openbsd-and-modern-laptop.html

Is your BIOS set to RAID for the HDD? If so try setting it to AHCI in the BIOS.

OpenBSD 6.5 on Clevo W840SU: BIOS hangs when booted via (m)SATA

[finkfox]

Dear Community. 
 

   
I'm trying to run OpenBSD on a Clevo W840SU laptop. After a successful install  
   
and starting the machine the BIOS hangs. That is, when the booting drive is 

connected via SATA/mSATA. When connected via USB, it works just fine.

The identical laptop model is mentioned as a working one 
in Peter Hansteen's blog (including a dmesg log) [1].   



A detailed documentation of the issue is given in the plain text document   
  
attached. 

 
So is this a broken BIOS issue?
What else could I try to get this to work?
How to debug this issue further?


   
I've been using GNU/Linux before and have had not problem with a hanging BIOS   
 
whatsoever. In fact it's still working without a problem on this machine.   

   




 
Thank you very much for your attention and help.
   

   
Fox

--
[1] https://bsdly.blogspot.com/2017/07/openbsd-and-modern-laptop.html
OpenBSD 6.5 on Clevo W840SU: BIOS hangs when disk attached via SATA
===

== Error Description

=== With BIOS UEFI disabled 

That is, BIOS Settings _Boot -> UEFI Setting -> UEFI Boot_ disabled.

* Successfully installed install65.fs from USB to SATA/mSATA connected disk
* With
** Fdisk MBR whole
** Disklabling auto

 Result

1. Upon restart system hangs showing only the American Megatrends logo and 
version.
2. CPU fan starts to turn up.
3. BIOS settings cannot be reached. (press/hold ESC key upon boot)

NOTE: Attaching the same disk via USB, BIOS boot does not hang, system can be 
successfully booted.  

=== With BIOS UEFI enabled

That is, BIOS Settings _Boot -> UEFI Setting -> UEFI Boot_ enabled.

* Successfully installed install65.fs from USB to SATA connected disk
* With
** Fdisk GPT whole
** Disklabling auto

 Result

1. Upon system start screen remains blank (not black) and goes in a restart 
loop.  
2. CPU fan starts to turn up.
3. BIOS settings cannot be reached. (press/hold ESC key upon boot)
 
NOTE: Attaching the same disk via USB, BIOS boot does not hang, system can be 
successfully booted.

== Machine Description

* Clevo W840SU
* American Megatrends Version 2.15.1236 2012
* ME FW Version 9.5.13.1706
* BIOS Version 1.03.02
* KBC/EC Firmware Revision 1.03.02

=== BIOS Settings

 Advanced

* Intel(R) Smart Connect Technology : disabled
* Intel(R) Rapid Start Technology : disabled
* SATA Mode : AHCI Mode
* Boot Logo: Disabled
* Power On Boot Beep: Enabled
* Battery Low Alarm Beep: Disabled

 Security

* TPM Configuration : disabled


== Things tried but did not work

=== Clear partition table

* Erase first 2M of disk before install 


dd if=/dev/zero of=/dev/sdx bs=2M count=1


=== Initialized EFI boot files with MBR

See https://marc.info/?m=15190459022533

Step 1 : Initialize MBR


newfs -t msdos sdNi
mount /dev/sdNi /mnt
mkdir -p /mnt/efi/boot
cp /usr/mdec/BOOT*.EFI /efi/boot/
umount /mnt
sync


Step 2 : install openbsd -> choose "OpenBSD" configure disk fdisk step (which 
supposedly does not alter the MBR)

Step 3 : reboot with and without UEFI enabled.

 Result

* MBR after successfull install

$ doas fdisk -v sd2

Primary GPT:
Not Found

Secondary GPT:
Not Found

MBR:
Disk: sd2   geometry: 121601/255/63 [1953525168 Sectors]
Offset: 0   Signature: 0xAA55
Starting Ending LBA Info:
 #: id