diff --git a/site/docs/hardware/dell9020.md b/site/docs/hardware/dell9020.md
index a07ee9b..82eac77 100644
--- a/site/docs/hardware/dell9020.md
+++ b/site/docs/hardware/dell9020.md
@@ -91,23 +91,62 @@ Kukri's patch is here:
 This patch, at this revision (patchset 31), is what Libreboot uses for this
 port.
 
-Graphics cards
+Graphics cards and IOMMU
 --------------
 
+IOMMU is buggy for some reason (we don't know why yet), when you plug in
+a graphics card. The graphics card simply won't work. On some of them,
+you can use the console but as soon as you start xorg, it will just b0rk.
+
+Current Libreboot revisions *disable IOMMU by default*, on this board. The
+coreboot code for initialising IOMMU was modified by the Libreboot project, to
+make it a toggle. IOMMU works fine if you use only Intel graphics.
+
+The way coreboot works is this: if vt-d is present on the CPU, it enables an
+IOMMU, and only if vt-d is present. This is still the behaviour in Libreboot,
+but Libreboot adds an additional check: if `iommu` is not set in nvram, it
+defaults to on, but if it's set to disabled, then IOMMU is not initialised.
+
+On all other Haswell boards, LIbreboot enables IOMMU by default. To enable
+it on the 9020, do this on your ROM:
+
+	nvramtool -C libreboot.rom -w iommu=Enable
+
+Then flash the ROM image. You can find nvram
+under `src/coreboot/default/util/nvramtool`. Do this in lbmk if you don't
+already havse `src/coreboot/default/`:
+
+	./update trees -f coreboot default
+
+Then do this:
+
+	make -C src/coreboot/default/util/nvramtool
+
+The binary `nvramtool` will then live in that directory. More information
+available in [Libreboot build instructions](../build/). Information about
+dumping/flashing the ROM can be found
+in [Libreboot flashing instructions](../install/)
+and [Libreboot external flashing instructions](../install/spi.md).
+
+NOTE: If IOMMU is enabled, you can still use a graphics card, but you must
+pass this on the Linux cmdline paramaters: `iommu=off`
+
+NOTE2: Libreboot uses a *static option table* on all boards that have nvram,
+which is why you must use the `-C` option on your ROM, to change the static
+table that is baked into it.
+
 On current lbmk master, graphics cards *do* work. The option to hide PEG
 devices from MRC was disabled. Now when you insert a graphics card, the
 onboard Intel GPU is disabled and the graphics card is used instead.
 
-NOTE: You must set `iommu=off` in your linux cmdline. For instance, set this
-in `/etc/default/grub` and regenerate your GRUB config. With the IOMMU turned
-off, graphics cards work fine. Otherwise, with IOMMU turned on, you might get
-this error:
+Here is an example of the type of errors we got when testing graphics cards
+with IOMMU enabled:
 
 <https://av.vimuser.org/error.jpg>
 
-NOTE2: You *can* use the onboard Intel GPU (without a graphics card inserted),
-and leave IOMMU turned on. You only need to disable the IOMMU when a graphics
-card is inserted.
+We believe the native MRC replacement may work better on graphics card with
+IOMMU turned on. This will be enabled in a future Libreboot release, if not
+already supported.
 
 7020 compatibility
 ------------------