Bootable Partition size in NT

I have a HP 900 laptop that somehow has a boot partition of 9.72gigs. How is that possible? I thought NT only allowed a maximum boot partition of up to 8gigs. I am using the NT unattended install and it is configured to make the boot partition (c: drive) the “default” size. This is the only machine I have seen this on. I have not been able to find anything on technet except that the NT boot partition is limited. Does anyone have any ideas? Thanks.