My Y480 factory pre-assembled Win7, now after a long time, the system has been re-installed into win8.1, but the partition table also has an OEM partition. It should be a preinstalled system backup, directly tied to the recovery key next to the laptop power key ... However, since the system has been finished by me, the key has not been used very early, think about the decision to delete this OEM partition.
The hidden partitioning method set by each major vendor should be similar, so you can refer to this.
Or, understand the principle of the normal partition to hide it is also possible oh, after hiding, do not know this method of people should be difficult to crack out.
The OEM partition is actually just doing the hidden partition, because the partition set is unreadable, so the system partition table in Disk Management shows 100% available, and then there is no way to manipulate it.
The system comes with the DiskPart tool to complete the management.
Open cmd, enter DiskPart
Input? can view Help
List disk displays all the information about the disks on the current system
Select Disk 0 selects the required hard drive according to the number ... It's like this on my computer.
Rescan re-scanning configuration information
List partition displays partition information for the current hard disk
Select Partition 4 is also based on the partition number selection, all my partitions are primary partitions, partition 4 is the type of OEM, this is the partition to be done.
After you finish selecting partitions
Deatil Partition Show partition details
Normal partition type: 4 is fat32,7 to NTFS
The hidden OEM partition type is typically 11 or 12, and setting to 11 shows the primary partition
So set id=7 changes the partition type to 7, which is the normal NTFS type.
After the change, the hidden partition is displayed and can be used as normal.
You can see that the OEM partition that was not shown in the disk Management has become Lenovo_part (f), then it is possible to remove the partition and release the space to other disks.
Win7, WIN8 after the system management tools inside the disk management is quite good.
OEM partition solutions for branded notebooks preinstalled in Windows (Lenovo)