diff --git a/usage/ideterqua.rst b/usage/ideterqua.rst
index d1e0878..671e58f 100644
--- a/usage/ideterqua.rst
+++ b/usage/ideterqua.rst
@@ -1,4 +1,4 @@
-Tertiary and Quaternary IDE
+Tertiary and quaternary IDE
 ===========================
 
 The additional tertiary and quaternary IDE controllers, enabled through the :ref:`settings/peripherals:Tertiary / Quaternary IDE Controller` settings, may require manual configuration of guest operating systems, which is outlined in this page. They are also **not bootable**, except on machines equipped with MR BIOS.
@@ -13,14 +13,47 @@ The following system resources are used by these additional controllers:
 |Quaternary|01E8h        |03EEh          |11 |
 +----------+-------------+---------------+---+
 
-.. important:: While the IRQ for each channel can be changed through its respective *Settings* button on :ref:`settings/peripherals:Tertiary / Quaternary IDE Controller`, most operating systems do not allow IDE controllers to use custom IRQs.
+.. note:: While the IRQ for each channel can be changed through its respective *Settings* button on :ref:`settings/peripherals:Tertiary / Quaternary IDE Controller`, most operating systems do not allow legacy (ISA or VLB) IDE controllers to use custom IRQs.
 
-Windows NT (including 2000, XP and newer)
------------------------------------------
+.. _bios:
 
-The Windows NT family will detect and enable both additional channels at installation time.
+BIOS support
+------------
 
-Additionally, they can be enabled after the fact through the *Add New Hardware* control panel, by adding a *Generic IDE/ESDI Hard Disk Controller* device for each channel. Configuration 000x corresponds to the **tertiary** channel, while Configuration 000x corresponds to the **quaternary** channel.
+The tertiary and quaternary controllers are only supported (partially or fully) by some BIOSes. The following table lists all BIOSes emulated by 86Box which are known to support these controllers:
+
++--------------------------------+-------------+-----------+-------------------------------+
+|BIOS                            |Seen in BIOS?|Bootable? *|:ref:`Windows NT support? <nt>`|
++================================+=============+===========+===============================+
+|American Megatrends             |No           |No         |Yes                            |
++--------------------------------+-------------+-----------+-------------------------------+
+|Phoenix - AwardBIOS v6.00PG \*\*|No           |No         |Yes                            |
++--------------------------------+-------------+-----------+-------------------------------+
+|MR BIOS                         |Yes          |Yes        |Yes                            |
++--------------------------------+-------------+-----------+-------------------------------+
+
+| \* Includes support for DOS and other real mode operating systems.
+| \*\* Award Modular BIOS v6.00PG and all other versions before it do not have any support.
+
+Windows 95, 98 and Me
+----------------
+
+TBD
+
+.. _nt:
+
+Windows NT, 2000, XP and newer
+------------------------------
+
+The Windows NT family will detect and enable both additional channels at installation time *only if* supported by the BIOS (see the *Windows NT support?* column on :ref:`the table above <bios>`).
+
+.. note:: If you install the system to a hard disk on one of the additional channels, it will not be bootable if the BIOS doesn't support booting from these channels (see the *Bootable?* column).
+
+Alternatively, the additional channels can be enabled after the system is installed:
+
+* **Windows NT 4.0:** TBD.
+* **Windows 2000:** go to the *Add New Hardware* control panel and add a *Generic IDE/ESDI Hard Disk Controller* device for each additional channel. Configuration 000x corresponds to the **tertiary** channel, while Configuration 000x corresponds to the **quaternary** channel.
+* **Windows XP:** TBD. (IDE/ESDI not listed - let PnP do the job?)
 
 Linux
 -----