The BIOS chip can be regarded as the “glue” that binds the hardware to the operating system. If the BIOS doesn't recognize the operating system or the hardware it communicates with, you're sure to have problems.
Because the BIOS chip bridges hardware to the operating system, you will need to upgrade the BIOS whenever your current BIOS version is unable to properly support
New hardware, such as large ATA/IDE hard drives and different types of removable-storage drives
New operating systems and features
New BIOS options
Although software drivers can be used as workarounds for hard drive BIOS limitations, a true BIOS upgrade is the best solution for hard disk control, and the only solution if your BIOS can't handle new processors ...