4TB HDD is acting strange?

So I'm working on a NAS, but one of my HDDs, being a 4TB drive, has been acting funny. Previously when it was in my main PC, it would prevent my PC from booting, mind you, it wasn't the drive that had my OS on it. The drive also only allows for a certain size of files before it decides it won't actually transfer the files (I'm not sure what file size is the max though) I've tried formatting in NFTS and Exfat and Im really not sure what the problem is. The drive is a Seagate BarraCuda 4TB HHD. I don't want to use it in my NAS in case it breaks anything or I lose files from corruption.