In older PCs BIOS doesn’t support hard drives over 8 GB even though the hard drive is correctly recognized on setup. So, it will be correctly recognized on setup but when you format it, it will only format as 8 GB. This problem is caused by a BIOS limitation, similar to the famous 504 MB limit that existed many years ago.
There are two solutions for this problem:
1. BIOS upgrade: This is the best option. If your motherboard uses a Flash-ROM chip you can reprogram it in order to solve this limitation. You can learn how to do this reading our tutorial How to Do a BIOS Upgrade.
2. If the ROM memory from your motherboard doesn’t allow an upgrade the solution is to use a special formatting software (a.k.a. Disk Manager) which is distributed by the hard drive manufacturer. This program formats the hard drive and installs a driver on the hard disk’s MBR and boot sector which is loaded every time you turn your PC on before loading the operating system, allowing to have access to the full capacity of the hard drive. Below we linked these programs for the most common hard drive manufacturers.