diff --git a/example-os/.gitignore b/example-os/.gitignore
index 605e551..6dc21ac 100644
--- a/example-os/.gitignore
+++ b/example-os/.gitignore
@@ -4,4 +4,6 @@
 /os.reasm
 /os.reasm.disasm
 /os.file
+/os.fdisk
 /os.arm.disasm
+/os.zip
diff --git a/example-os/Makefile b/example-os/Makefile
index 7b8d6c2..01c0f61 100644
--- a/example-os/Makefile
+++ b/example-os/Makefile
@@ -2,14 +2,15 @@ os_filename = os.bat
 tests = test/qemu-system-i386 test/qemu-system-arm test/virtualbox test/bochs test/gui-sh test/dosbox
 
 os_image_size_kb = 1440
-os_sectors_before_partition = 720
+os_partition_start_sectors = 3
+os_partition_size_sectors = 717 # 720 - start
 # CHS parameters for 1.44 MB floppy disk
 os_floppy_chs_h = 2
 os_floppy_chs_s = 9
 
 .PHONY: all
 # all: os.arm.disasm
-all: $(os_filename) os.ndisasm.disasm os.reasm.asm os.reasm os.file .gitignore Makefile
+all: $(os_filename) os.ndisasm.disasm os.reasm.asm os.reasm os.file os.fdisk .gitignore Makefile
 
 ../deploy-screenshots: Makefile
 	mkdir -p $@
@@ -19,16 +20,22 @@ $(os_filename): os.asm ../deploy-screenshots Makefile
 	rm -f $@
 	nasm -o $@ $<
 	mformat -v "Example OS" \
-	 -T $$(($(os_image_size_kb)*1024/512-$(os_sectors_before_partition))) \
+	 -T $$(($(os_partition_size_sectors))) \
 	 -h $(os_floppy_chs_h) \
 	 -s $(os_floppy_chs_s) \
-	 -i "$@@@$$(($(os_sectors_before_partition)*512))"
-#	mcopy … "$@@@$$(($(os_sectors_before_partition)*512))"
+	 -i "$@@@$$(($(os_partition_start_sectors)*512))"
+#	mcopy … "$@@@$$(($(os_partition_start_sectors)*512))"
+	zip os.zip $@
+	dd seek=$$(($(os_image_size_kb)*1024-$$(wc -c os.zip | cut -d ' ' -f 1))) bs=1 if=os.zip of=$@
+	zip --adjust-sfx $@
 	chmod a+x-w $@
 
 os.file: $(os_filename) Makefile
 	file -kr $< > $@
 
+os.fdisk: $(os_filename) Makefile
+	fdisk -l $< > $@
+
 os.ndisasm.disasm: $(os_filename) Makefile
 	../utils/compact-ndisasm.sh $< $@
 
@@ -49,7 +56,7 @@ os.reasm: os.reasm.asm $(os_filename) Makefile
 
 .PHONY: clean
 clean: Makefile
-	rm -f $(os_filename) os.ndisasm.disasm os.reasm.asm os.reasm os.file os.arm.disasm
+	rm -f $(os_filename) os.ndisasm.disasm os.reasm.asm os.reasm os.file os.arm.disasm os.zip
 
 .gitignore: Makefile
 	echo /$(os_filename)    >  $@
@@ -58,11 +65,17 @@ clean: Makefile
 	echo /os.reasm          >> $@
 	echo /os.reasm.disasm   >> $@
 	echo /os.file           >> $@
+	echo /os.fdisk          >> $@
 	echo /os.arm.disasm     >> $@
+	echo /os.zip            >> $@
 
 .PHONY: test
-test: $(tests) all Makefile
+test: $(tests) test/zip all Makefile
 
 .PHONY: $(tests)
 $(tests): $(os_filename) ../deploy-screenshots Makefile
 	cd .. && ./utils/gui-wrapper.sh 800x600x24 ./$@.sh example-os/$<
+
+.PHONY: test/zip
+test/zip:
+	unzip -t os.zip
diff --git a/example-os/os.asm b/example-os/os.asm
index 8ab9c3f..85b77cf 100644
--- a/example-os/os.asm
+++ b/example-os/os.asm
@@ -53,7 +53,7 @@ db "ExOSxx"        ;; 0x1b8 unique disk ID (4 bytes, can be any value)
 ;;; 3 bytes End Head Sector Cylinder (8 bits + 6 bits + 10 bits)
 ;;; 4 bytes LBA offset
 ;;; 4 bytes LBA length
-db 0x80, 0x00, 0x00, 0x00,  0x01, 0x00, 0x00, 0x00,  0x03, 0x00, 0x00, 0x00,  0x3d, 0x0b, 0x00, 0x00 ;; 0x1be p1
+db 0x80, 0x00, 0x00, 0x00,  0x01, 0x00, 0x00, 0x00,  0x40, 0x0b, 0x00, 0x00,  0x3d, 0x0b, 0x00, 0x00 ;; 0x1be p1
 db 0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00 ;; 0x1ce p2
 db 0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00 ;; 0x1de p3
 db 0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00 ;; 0x1ee p4