diff --git a/src/include/86box/vid_voodoo_codegen_x86-64.h b/src/include/86box/vid_voodoo_codegen_x86-64.h
index b7028c7d7..a9701860c 100644
--- a/src/include/86box/vid_voodoo_codegen_x86-64.h
+++ b/src/include/86box/vid_voodoo_codegen_x86-64.h
@@ -2327,7 +2327,7 @@ voodoo_generate(uint8_t *code_block, voodoo_t *voodoo, voodoo_params_t *params,
                     addlong(offsetof(voodoo_state_t, z));
                     addbyte(0xc1); /*SHR EAX, 12*/
                     addbyte(0xe8);
-                    addbyte(12);
+                    addbyte(20);
                     addbyte(0x25); /*AND EAX, 0xff*/
                     addlong(0xff);
 #if 0