QUOTE (Longhaul @ May 27 2004, 11:41 AM)
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The 4 gig limit is a limit in the bios of the machine. It is not the disks fault. The original install when NT 4.0 came out is that it could not have a boot disk greater than 4 gigs with out a newer bios.
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That limit was inherent to the FAT16 file system, which had a 16-bit limit for addresses in the file allocation table. 2^16 sectors of 2^16 bytes each = 4G. 65536 sectors of 65536 bytes each. But DOS, which could only address one 64k segment at a time, couldn't handle a 65536 byte data frame, because it wouldn't have any memory left in that page frame for OS instructions. That's why formatting a 4G FAT16 with NT4 gave you a warning that it might be incompatible with DOS. So DOS' formatting ability was capped at 2^16 sectors of 2^15 bytes = 2048M.
NT4 could handle a 64k data frame, but the FAT16 file system couldn't go any higher than 2^16*2^16. The ExtendOEMPartition does a conversion of the 4G FAT16 partition to NTFS, then extends it - FAT16 is capped at 4G regardless of your OS. Prior to the ATAPI.SYS driver in NT4SP3, the next limit for an NT4 boot partition was the 2^10 cylinder addressing limit, which was in BIOS. 2^10 cylinders * 255 heads * 63 sectors/cylinder * 512 bytes/sector = 8.4G limit. Some BIOSes like IBMs cropped this at 7.8G. Then INT13h extensions came around, and there was much rejoicing.
That's just from memory - only slightly peripheral to the topic.
-syrynxx