--- /dev/null
+[[!meta title="Portal on Linux: fix black screen without textures"]]
+[[!meta author="rohieb"]]
+[[!meta license="CC-BY-SA 3.0"]]
+[[!img defaults size=x200]]
+
+**Problem:** I just bought [Portal][] for Linux. When I start the game on my
+AMD64 laptop with Debian testing, I only see black objects, and a few light
+stripes in between. Everything else works, I can hear sound, I can interact with
+objects, and I can look and around, in which case the stripes also move in the
+right directions, so they seem to be speckles or reflections rendered on
+objects, and only the textures are missing.
+
+**Solution:** Searching the Steam forums resulted in nothing (who would have
+guessed), but [this forum post][post] suggested to update Mesa to version 9.2
+and install `libtxc-dxtn` or `libtxc-dxtn-s2tc0`. This packages were not
+installed on my system, and the description for the package says that it is used
+for texture compression, so it seems to be related. So I first tried to install
+the i386 version:
+
+ aptitude install libtxc-dxtn-s2tc0 libtxc-dxtn-s2tc0:i386
+
+After restarting Portal, the problem was gone, so I refrained from updating my
+Mesa :-)
+
+Before and after images:
+<div class="gallery">
+[[!img testchmb_a_000000.jpg alt="Before"]]
+[[!img testchmb_a_000002.jpg alt="After"]]
+</div>
+
+[Portal]: http://store.steampowered.com/app/400/
+[post]: https://01.org/linuxgraphics/comment/358#comment-358
+
+[[!tag quickfix howto Portal games Linux Linux_gaming Debian Debian_testing
+ Mesa libtxc-dxtn]]