diff --git a/tests/guests/Makefile.am b/tests/guests/Makefile.am
index a05dceb84..82cb9b81c 100644
--- a/tests/guests/Makefile.am
+++ b/tests/guests/Makefile.am
@@ -96,3 +96,8 @@ guest-aux/windows-system: guest-aux/windows-system.reg
 	cp guest-aux/minimal-hive $@-t
 	hivexregedit --merge $@-t --prefix 'HKEY_LOCAL_MACHINE\SYSTEM' $<
 	mv $@-t $@
+
+# Don't construct the guests in parallel.  In automake 1.13, check_DATA
+# was changed so it can now run in parallel, but this causes everything
+# to fall over on machines with limited memory.
+.NOTPARALLEL: