As long as the bios is recognizing the drive you may have to have XP scan
for it. It is not being picked up automatically.
Right click on My Computer. Left click on Manage. Click on Disk Management
in the left window. Click on Action menu item. Click on Rescan Disks in
the dropdown. You should see the WIN 98 drive in the right window once the
scan stops. If you see the drive in the right window it should tell you
that it is Healthy and that it has a FAT32 file system.
If it does not show up, close everything down and reboot the computer again.
Attempt the rescan again.
If it still doesn't work, right click on My Computer. Click on Properties.
Click on the Hardware tab. Click on the Device Manager button. Click the +
sign next to disk drives. If the disk shows here without a yellow ! next to
it you should be able to see it in Explorer. If not, you have a problem
with your data cable or jumper settings. If the new drive is a Western
Digital you must set its jumper to Master with Slave not simply
Master/Single. The old drive needs to be set to Slave.
You may also use cable select on both drives but make sure your Master drive
is at the end of the cable and the slave drive is in the middle positon on
the cable. You should be using an 80 wire cable also.