diff --git a/conf/distro/zephyr.conf b/conf/distro/zephyr.conf
index 9f57c9e..4a832db 100644
--- a/conf/distro/zephyr.conf
+++ b/conf/distro/zephyr.conf
@@ -11,5 +11,3 @@ TCLIBCAPPEND = ""
 TEST_TARGET = "QemuTargetZephyr"
 TEST_SUITES = "zephyr"
 
-BOARD_arm ?= "qemu_cortex_m3"
-BOARD_x86 ?= "qemu_x86"
diff --git a/recipes-kernel/zephyr-kernel/zephyr-kernel-common.inc b/recipes-kernel/zephyr-kernel/zephyr-kernel-common.inc
index 6fe44b5..30c1a5a 100644
--- a/recipes-kernel/zephyr-kernel/zephyr-kernel-common.inc
+++ b/recipes-kernel/zephyr-kernel/zephyr-kernel-common.inc
@@ -4,6 +4,9 @@
 # filesystem.
 IMAGE_NO_MANIFEST = "1"
 
+# Zephyr BOARD is basically our MACHINE, except we must use "-" instead of "_"
+BOARD="$(echo ${MACHINE} | tr - _)"
+
 # oe_runmake isn't used because of the make -e causing issues with some
 # make variables.
 MAKE_COMMAND = "make -j V=1 BOARD=${BOARD} CROSS_COMPILE=${CROSS_COMPILE}"