---
title: ASUS KFSN4-DRE server/workstation board 
x-toc-enable: true
...

This is a server board using AMD hardware (Fam10h). It can also be used
for building a high-powered workstation. Powered by osboot.

Flashing instructions can be found at
[../install/\#flashrom](../install/#flashrom)

Form factor {#formfactor}
===========

These boards use the SSI EEB 3.61 form factor; make sure that your case
supports this. This form factor is similar to E-ATX in that the size is
identical, but the position of the screws are different.

Flash chips {#flashchips}
===========

These boards use LPC flash (not SPI), in a PLCC socket. The default
flash size 1MiB (8Mbits), and can be upgraded to 2MiB (16Mbits).
SST49LF080A is the default that the board uses. SST49LF016C is an
example of a 2MiB (16Mbits) chip, which might work. It is believed that
2MiB (16Mbits) is the maximum size available for the flash chip.

*DO NOT hot-swap the chip with your bare hands. Use a PLCC chip
extractor. These can be found online. See
<http://www.coreboot.org/Developer_Manual/Tools#Chip_removal_tools>*

Native graphics initialization {#graphics}
==============================

Native graphics initialization exists (XGI Z9s) for this board.
Framebuffer- and text-mode both work. A serial port is also available.

Memory
======

DDR2 533/667 Registered ECC. 16 slots. Total capacity up to 64GiB.

Hex-core CPUs {#hexcore}
=============

PCB revision 1.05G is the latest version of this board and the best one
(the revision number is be printed on the board), if you want to use
dual hex-core CPUs (Opteron 2400/8400 series), though only two board
configurations are believed to support them. Other revisions are
believed to only support dual quad-core CPUs.

To be sure your board supports a CPU check the official ASUS website here:
<https://www.asus.com/support/cpu_support>. Note: not all CPUs are listed.

If you are running a Hex-Core CPU on any board version, please contact us.

Board configurations {#configurations}
==============
There are 7 different configurations of this board: "standard", 2S, iKVM,
iKVM/IST, SAS, SAS/iKVM and SAS/iKVM/IST.

The 2S boards have two PCI-E slots with the numbers of lanes shared,
making each slot have 8 lanes.

The iKVM boards are so called because they offer a remote real-time access
to the machine through a removable PCI management card, their hardware is
the same as the non-iKVM ones.

The SAS versions have a 4-port SAS controller and a four 7-pin SAS connectors
instead of the PCI-E 8x slot which is present in all the other board configurations.
Note: the SAS functionality is **not supported** by osboot.

The IST versions with PCB revision 1.05G are the ones who are believed to
support the six core Opteron Istanbul processors (2400 and 8400 series).

Current issues {#issues}
==============

-   There seems to be a 30 second bootblock delay (observed by
    tpearson); the system otherwise boots and works as expected. See
    [text/kfsn4-dre/bootlog.txt](text/kfsn4-dre/bootlog.txt) - this uses
    the 'simple' bootblock, while tpearson uses the 'normal'
    bootblock, which tpearson suspects may be a possible cause. This
    person says that they will look into it. [This
    config](http://review.coreboot.org/gitweb?p=board-status.git;a=blob;f=asus/kfsn4-dre/4.0-10101-g039edeb/2015-06-27T03:59:16Z/config.txt;h=4742905c185a93fbda8eb14322dd82c70641aef0;hb=055f5df4e000a97453dfad6c91c2d06ea22b8545)
    doesn't have the issue.

-   Text-mode is jittery and it may not be usable, so it's recommended
    to flash the BIOS with the coreboot frame-buffer image (kfsn4-dre_corebootfb.rom).
    The jitter disappears if using KMS once the kernel starts, but it will 
    remain, if booting the kernel in text-mode.

-   Booting from USB mass storage devices is not possible; neither GRUB
    nor SeaBIOS detect USB drives when present. USB keyboards function
    under both GRUB and SeaBIOS, albeit slowly under GRUB (several seconds per
    character typed).

-   To install an operating system you will need a hard disk
    with a pre-installed OS otherwise you have to plug in another hard disk or
    a CD/DVD reader in order to boot a copy of the installer of your OS, since
    the USB booting doesn't work.

Other information
=================

[specifications](https://web.archive.org/web/20181212180051/http://ftp.tekwind.co.jp/pub/asustw/mb/Socket%20F/KFSN4-DRE/Manual/e3335_kfsn4-dre.pdf)