diff --git a/src/sys/boot/bootsec.asm b/src/sys/boot/bootsec.asm
index b84f139..b13593b 100755
--- a/src/sys/boot/bootsec.asm
+++ b/src/sys/boot/bootsec.asm
@@ -187,7 +187,7 @@
 	cli		; No interrupts please at all
 	lgdt    [gdtinfo]
 	mov     ecx, cr0
-	inc     cx
+	or	ecx, 1       ; set PE bit
 	mov     cr0, ecx
 	mov     ax, flat_data-gdt_table
 	mov     ds, ax