diff --git a/README.md b/README.md
index 46f35e9..d322674 100644
--- a/README.md
+++ b/README.md
@@ -3,7 +3,21 @@
 Build script for archlinux instructionset enabled repos.
 All packages are build with -march=<cpu-set> and -O3. Some packages will not build with -O3, they will just be provided from the official repos as usual.
 
+## Check your system for support
+
+**Important**: Before you enable any of these repos, check if your system supports x86-64-v3. You can do that with `/lib/ld-linux-x86-64.so.2 --help`. If you don't check beforehand you might be unable to boot your system anymore and need to downgrade any package that you may have upgraded.
+
+Example output snippet for a system supporting up to `x86-64-v3`:
+
+```
+Subdirectories of glibc-hwcaps directories, in priority order:
+  x86-64-v4
+  x86-64-v3 (supported, searched)
+  x86-64-v2 (supported, searched)
+```
+
 ## Enable Repos
+
 To enable these complement repos you need to add them above the regular repos in `/etc/pacman.conf`
 
 ### Example pacman.conf