how does block mode give faster access to a hard drive? how can u disable block mode?

Answer 1

A hard drive operates by principle in block mode so this can not be turned off. What you probably wonder about is the block size and data transfer optimization settings.

The block size will determine how much data can be read in one operation. Normally, the lesser operations, the faster it goes so you want it as better as it can go in normal circumstances.

The BIOS configuration is often accessed by pressing DEL or F1 on startup. From there you'll have to search a bit since I don't know which BIOS you have.