Cache Buffer Size question

[Joyride]

What exactly is it and just how much better is 8mb over 2mb

I know there are tons of HD with 2mb cache buffer but how many (other then the 120 gb at Dell) have 8mb cache?

 

[MajinVegitto]

Higher data transfer rates. Western Digital makes one line of 8mb cache buffer drives. 80, 100, 120 GB sizes.