diff --git a/metropolis/cli/metroctl/core/install.go b/metropolis/cli/metroctl/core/install.go
index 31fe4a0..5a41fc7 100644
--- a/metropolis/cli/metroctl/core/install.go
+++ b/metropolis/cli/metroctl/core/install.go
@@ -47,7 +47,8 @@
 	if err != nil {
 		return fmt.Errorf("failed to read OS image: %w", err)
 	}
-	bootPath, err := install.EFIBootPath(osImage.Config.ProductInfo.Architecture())
+	architecture := osImage.Config.ProductInfo.Architecture()
+	bootPath, err := install.EFIBootPath(architecture)
 	if err != nil {
 		return err
 	}
@@ -88,6 +89,9 @@
 	if err != nil {
 		return fmt.Errorf("target device has invalid geometry: %w", err)
 	}
+	if architecture == "x86_64" {
+		partTable.BootCode = install.BootcodeX86
+	}
 	esp := gpt.Partition{
 		Type: gpt.PartitionTypeEFISystem,
 		Name: "MetropolisInstaller",
diff --git a/metropolis/installer/install/BUILD.bazel b/metropolis/installer/install/BUILD.bazel
index 1a0fed3..2cd2fdc 100644
--- a/metropolis/installer/install/BUILD.bazel
+++ b/metropolis/installer/install/BUILD.bazel
@@ -3,6 +3,9 @@
 go_library(
     name = "install",
     srcs = ["install.go"],
+    embedsrcs = [
+        "//metropolis/node/bios_bootcode",  #keep
+    ],
     importpath = "source.monogon.dev/metropolis/installer/install",
     visibility = ["//visibility:public"],
     deps = [
diff --git a/metropolis/installer/install/install.go b/metropolis/installer/install/install.go
index dda3b7a..4d93723 100644
--- a/metropolis/installer/install/install.go
+++ b/metropolis/installer/install/install.go
@@ -6,6 +6,7 @@
 package install
 
 import (
+	_ "embed"
 	"fmt"
 	"io"
 
@@ -53,6 +54,9 @@
 	return "EFI/BOOT/" + bootName, nil
 }
 
+//go:embed metropolis/node/bios_bootcode/boot.bin
+var BootcodeX86 []byte
+
 // PartitionSizeInfo contains parameters used during partition table
 // initialization and, in case of image files, space allocation.
 type PartitionSizeInfo struct {
@@ -93,9 +97,6 @@
 	// PartitionSize specifies a size for the ESP, Metropolis System and
 	// Metropolis data partition.
 	PartitionSize PartitionSizeInfo
-	// BIOSBootCode provides the optional contents for the protective MBR
-	// block which gets executed by legacy BIOS boot.
-	BIOSBootCode []byte
 }
 
 type plan struct {
@@ -179,7 +180,10 @@
 	}
 
 	params.tbl.ID = params.DiskGUID
-	params.tbl.BootCode = p.BIOSBootCode
+	architecture := p.OSImage.Config.ProductInfo.Architecture()
+	if architecture == "x86_64" {
+		params.tbl.BootCode = BootcodeX86
+	}
 	params.efiPartition = &gpt.Partition{
 		Type: gpt.PartitionTypeEFISystem,
 		Name: ESPLabel,
@@ -193,7 +197,7 @@
 		return nil, err
 	}
 	// Place the A/B loader at the EFI bootloader autodiscovery path.
-	params.efiBootPath, err = EFIBootPath(p.OSImage.Config.ProductInfo.Architecture())
+	params.efiBootPath, err = EFIBootPath(architecture)
 	if err != nil {
 		return nil, err
 	}