Re: 28-bit LBA BIOS and 48-bit LBA XP - Can I use my 160GB hard disk safely?

I wouldn't trust it and to tell you the honest truth I don't know how Windows can properly see all of your disk if the BIOS cannot see it. There are two necessities or requirements for Windows XP to properly identify and use hard disks larger than 137GB. One is that you have at least SP1 installed and the other is that the BIOS be 48-bit LBA aware. I have never heard of one working without the other. The only way around the BIOS requirements would be to place the disk on an independent third party controller. I'm not sure what is going on with your pc and why it seems to defy the above 2 requirements.

John


JS wrote:

That's not what I ask. I know how to partition disk. Auctually I already partitioned this disk. My worry is whether my 28-bit LBA BIOS will screw up my data.
"Rich Barry" <rbarry@xxxxxxxxxxxx> wrote in message news:46d75b45$0$32469$4c368faf@xxxxxxxxxxxxxxxxx

Rt Click MyComputer>select Manage>Storage>Disk Management. Rt click the Unallocated Space and select create Logical Partition (drive). That should take care of
the remaining Drive Space. You will wind up with two partitions C: and D:


"JS" <J@S> wrote in message news:Od5xiX16HHA.4816@xxxxxxxxxxxxxxxxxxxxxxx

I recently upgraded my notebook with a 160GB hard disk. However in BIOS I see only 137GB. I know it is because the BIOS is only so-called '28bit' LBA. The notebook is of 4 years old and there will be no more BIOS update.
When I install XP (SP2) on this HD, I still see 160GB in XP. I heard it is because the driver in XP SP2 (atapi.sys) is 48-bit LBA already so it can recognize and access all 160GB disk.
But does this mean I can ignore the BIOS limitation and fully utilize 160GB in XP? I also heard some people with similar HD upgrade suffered data loss or system destruction because as something in the system doesn't support 48-bit, when writing to disk, it wraps back to first tracks and destroys MBR, boot sectors etc. But I don't know whether it was because BIOS didn't support 48-bit.
So my question is, with 28-bit BIOS, can I safely use 160GB disk with XP Sp2?
I read many articles, including Microsoft ones, that state that besides the OS 48-bit LBA support, BIOS must also support 48-bit LBA. But I also heard that, BIOS is only active when booting up the PC, once it passes to OS, it should be the OS that manages the disk. So, even though in BIOS I see only 137GB, it should not affect OS activities as long as OS supports 48-bit LBA. So I am a bit confused: As OS can recognize 160GB, why BIOS matters? In what situation can a 28-bit LBA BIOS destroy a 160GB disk?
I heard that some people say 'as long as the midpoint of the partition falls below 137GB, the BIOS will be able to boot from that partition' because the midpoint is where the MFT mirror is stored. But in XP the MFT mirror is stored at the end of partition?








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