diff --git a/profiles/calculate/make.conf/amd64/make.defaults b/profiles/calculate/make.conf/amd64/make.defaults
index f82246a33..9d52e6942 100644
--- a/profiles/calculate/make.conf/amd64/make.defaults
+++ b/profiles/calculate/make.conf/amd64/make.defaults
@@ -1,3 +1,3 @@
-CFLAGS="-O2 -march=k8 -pipe"
+CFLAGS="-O2 -march=x86-64 -pipe"
 CXXFLAGS="${CFLAGS}"
 CHOST="x86_64-pc-linux-gnu"