diff --git a/hw/i386/pc_piix.c b/hw/i386/pc_piix.c
index 4524e6b56e..9694f88057 100644
--- a/hw/i386/pc_piix.c
+++ b/hw/i386/pc_piix.c
@@ -326,6 +326,7 @@ static void pc_compat_1_7(MachineState *machine)
     smbios_defaults = false;
     gigabyte_align = false;
     option_rom_has_mr = true;
+    legacy_acpi_table_size = 6414;
     x86_cpu_compat_disable_kvm_features(FEAT_1_ECX, CPUID_EXT_X2APIC);
 }