First of all the correct spelling of the word is cache. Secondly, what you are talking about is not cache but buffer size. To answer your question, all I can tell you is when I had a hard drive with a 2 MB buffer it took a minute or two to load Windows XP Pro. When I upgraded to a hard drive with 8 MB buffer, Win XP Pro loads in under 30 seconds. I haven't had the opportunity of try a hard drive with 16 MB buffer size yet so I can't offer any advice on that configuration. Hope this helps.