There are limits in terms of harddrives and controllers:
- https://en.wikipedia.org/wiki/Logical_block_addressing
- http://www.pcworld.com/article/235088/everything_you_need_to_know_about_3TB_hard_drives.html
The first one appears at around 128GiB, so you should be safe as you had a 300GB Drive in there. The second one occurs at around 2.2TB, get a smaller disk and you should be safe.
Getting a 1TB Drive should be okay.
PS: I think you'll know about drive sizes (2.5", 3.5") and about the different interfaces...