On Thu, 2008-10-16 at 05:22 -0400, Bryan J. Smith wrote: > While virtually all other BIOS manufacturers solve the 256 head problem > by just using 255 in an 8-bit field (1111111), IBM-Levono does this > funky mess. The resulting 240 value (11110000) is completely divergent > from the rest of the industry.
Ugh, I was reading further, this isn't correct. My original post was more correct. It's been awhile since I looked at this, but I knew I was on the right track (I documented the whole issue long ago). It's that all other BIOS manufacturers now always use the 8-bit/255 heads (where its 0-255 = 256) and IBM-Levono continue to force the old, 5-bit/16 heads setting, period. Again, goes back to the '90s 24-bit versus original PC/AT 21-bit field. Both are ignored if you use newer Int13h disk services, but even IBM does not in its own utilities at the factory. ;) As I mentioned, always forcing 255 heads at the factory solves it, because both NT (as of 4.0 SP4+) and Linux always read the partition table geometry itself to determine the actual geometry it is using/assuming. It must still be 0-255 heads, or less, in the case of NT though (through 5.1 at least, possibly 6.0/6.1 too?). -- Bryan J Smith Professional, Technical Annoyance mailto:[EMAIL PROTECTED] http://www.linkedin.com/in/bjsmith ------------------------------------------------------------- Fission Power: An Inconvenient Solution _______________________________________________ lpi-examdev mailing list [email protected] http://list.lpi.org/cgi-bin/mailman/listinfo/lpi-examdev
