fdisk does not recognize my hard drive

on my previous toshiba satellite laptop, with 80GB hard drive, i was
able to load slackware 10.2 in the normal fashion. however, on my new
toshiba satellite, with 100GB har drive, i am informed when trying to
fdisk /dev/hda, that the disk has no recognizable partitiions, and the
size is reported as 668 MB.

winxp home is on both machines and taking about 80% of the space.

i have tried using partition magic, and have set up 20GB for slackware
with the following hard drive parameters: 255 h, 63 s, 12161 cyl, but
Slackware still insists that it is:

255 h, 63 s, 81 cyl!!

can anyone help me please?

thank you,

john

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