Recently the stock hard drive in my Dell XPS 15z has been having issues. I had to run chkdsk.exe multiple times to scan and attempt to repair bad sectors multiple times, in addition to multiple other diagnostics. Basically each test summed it up with I need a new hard drive but I'm not sure which are the most reliable.

I'm only familiar with western digital, so my knowledge of hardware in relation to hard drives is quite limited.

What should I be looking for?

Don't move your computer while the hard drive is spinning, imo. If you can afford a solid state drive they are nice for laptops since they don't suffer from this problem.

So you don't want anything less than a 7200 RPM HDD(Hard Disk Drive). Storage is whatever you want it to be. Seagate, Western Digital, Samsung all make decent drives and are the most common. Hitachi is an okay brand as well. If you can shell out the extra 100 or 200 go with a SSD (Solid State Drive) for many reasons, Mostly because the speed and performance of the drives are crazy fast.

thanks for the information zrod. I wasn't exactly sure which brands had optimal performance when it came to laptop hard drives.