Is this a safe procedure: http://www.supermicro.com/support/faqs/faq.cfm?faq=14720.

 

Can anyone confirm this?

I can't tell you if that is safe or not because that is NOT the process I tried.  I can tell you what I tried will BRICK your board so do NOT follow it.  I just took the 1.0C zip file I found and unzipped it to a bootable USB stick and used the ami.bat file to flash the bios. 

 

When I look at the command contained within the ami.bat file it looks like this:

AFUDOSU.EXE  %1  /P /B /N /R

When I look at the instructions you found they have an extra option "/K" which is suppose to be:

"/K - Program all non-critical blocks or ROM Holes"

 

So it should do more than what I did.  It is in the knowledge base and is listed as the correct procedure to downgrade so I would think it would work.  If you try it and have good results let me know because I have one board I need to downgrade and another I may need-to once I try to recover it with the recovery procedure.  I don't have a processor right now to load on my board or I would try it for you since my X9SCM-F is currently not being used.

...also, as far as I understand it,  the only way you can attempt to perform a downgrade is with a SandyBridge CPU, and NOT with a IvyBridge CPU !

...also, as far as I understand it,  the only way you can attempt to perform a downgrade is with a SandyBridge CPU, and NOT with a IvyBridge CPU !

Correct.  Ivy Bridge support is only in 2.0 so if you have that CPU you CAN'T downgrade the bios from 2.0.  If you have a Sandy Bridge CPU you should be able to go to 1.0 or 1.1.

I can confirm that this process works.  I just successfully downgraded my x9scm-f from bios v2.0a to bios v1.1a.  The command to downgrade to from v2.0a to v1.1a bios is "afudosu x9scm1.928 /p /b /n /r /k /fdt /mer /opr".  Note that the "x9scm1.928" text is the v1.1a ROM file.

 

The Supermicro instructions (link in OP) omit the ROM file in the command.  I appended the "/fdt /mer /op" at the end of the command line since I was unsure if I should run the second step without the other options "/p /b /n /r /k".

I can confirm that this process works.  I just successfully downgraded my x9scm-f from bios v2.0a to bios v1.1a.  The command to downgrade to from v2.0a to v1.1a bios is "afudosu x9scm1.928 /p /b /n /r /k /fdt /mer /opr".  Note that the "x9scm1.928" text is the v1.1a ROM file.

 

The Supermicro instructions (link in OP) omit the ROM file in the command.  I appended the "/fdt /mer /op" at the end of the command line since I was unsure if I should run the second step without the other options "/p /b /n /r /k".

 

Why did you downgrade? Did you have any problems running unraid or ESXi?

I downgraded to see if going from v2.0a to v1.1a would correct the slow write speed I am having with the X9SCM-F and v5.0-rc8a.  With testing I suspected the X9SCM-F bios was corrupt.  I reinstalled v2.0a but no change, so I wanted to see if downgrading to v1.1a would make any difference...it didn't.  I eventually plan to use EXSi on this server, but wanted to verify that I had v5.0-rc8a correctly running on this motherboard outside of EXSi first.

 

FYI - This thread summaries the slow read speed I'm having with the X9SCM-F and v5.0-rc8a:  http://lime-technology.com/forum/index.php?topic=22675.0