2 Replies Latest reply on Dec 6, 2009 10:37 AM by chizow

    8 GB section of 80GB X-25M became available for use

    smoothmole

      I have a new "Disk" available in Windows 7 - note it shows up as it's own disk, not a partition.  I recall reading an Ananadtech article explaining intel hides 8 GB on the drives from the user to ensure it is never totally filled - a storage area of some type for moving blocks of data around.  It looks to me like this area became accessible to me - I'm not sure how.  I'll describe the scenario leading to this event.

       

      1. I performed a clean install W7 Ultimate instal on a virgin X-25M G2 80GB drive (never initialized or formatted, but 02HD firmware installed).  The install created two partitions (on a single disk, and only one disk was listed as available during the instal).  The partitions that were automatically created are 100MB and 74.43 GB.  When viewing them in "Disk Managment"  they show up as two partitions under a single basic disc that is 74.53 GB.  MS AHCI drivers were installed - and I didn't change them.

       

      2. After a reboot (and possibly moving the sata port - I don't recall) - windows "found" and installed drivers for a new drive.  This surprised me.  The system said it needed to restart to use the new device - so I restarted.  I then opened disk mangment and sure enough - there is a new Disk listed.  It is 8 GB, currently not initialized - and I'm not going to initilize it for fear of creating a problem.

       

      So my questions are:

      Q1: has anyone else experienced this - do you have two drives (DRIVES, not partitions) recognized in Win7 from a single X25m? - one 74.53 GB and one 8 GB?

      Q2: Does anyone know what will happen if I initilize and use the 8GB drive?

        • 1. Re: 8 GB section of 80GB X-25M became available for use
          smoothmole

          So nobody has experienced this?  Can anyone from intel coment please?  Should I open a ticket and send the drive back for repair?

           

          Here is a link to the anandtech article I mentioned above describing the hidden space.

          http://www.anandtech.com/storage/showdoc.aspx?i=3531&p=9

           

          "Intel ships its X25-M with 7.5 - 8% more area than is actually reported to the OS. The more expensive enterprise version ships with the same amount of flash, but even more spare area. Random writes all over the drive are more likely in a server environment so Intel keeps more of the flash on the X25-E as spare area. You’re able to do this yourself if you own an X25-M; simply perform a secure erase and immediately partition the drive smaller than its actual capacity. The controller will use the unpartitioned space as spare area."

           

          Also here (this was a G1 drive, so amount may have been different).

          http://www.anandtech.com/cpuchipsets/intel/showdoc.aspx?i=3403&p=4

          "Intel actually includes additional space on the drive, on the order of 7.5 - 8% more (6 - 6.4GB on an 80GB drive) specifically for reliability purposes. If you start running out of good blocks to write to (nearing the end of your drive's lifespan), the SSD will write to this additional space on the drive. One interesting sidenote, you can actually increase the amount of reserved space on your drive to increase its lifespan. First secure erase the drive and using the ATA SetMaxAddress command just shrink the user capacity, giving you more spare area. "

          • 2. Re: 8 GB section of 80GB X-25M became available for use
            chizow

            I also recall reading about extra space being left to help reduce the effects of performance degradation, I believe OCZ does it as well (their 60GB drives for instance have 64GB physical).  I haven't seen the extra 8GB show up though as usable space much less an entirely new disk on either of my drives.  My guess is your LBA0 that has this partition/disk info was somehow compromised or changed.  You can maybe try poking around with an LBA editor or try a Secure Erase, then partition to 75GB and see if that fixes it.  If you use the 8GB, I don't think there's any adverse effects other than the onset of "full drive" performance degradation that much sooner.