I if anyone can say that a faster HD does load windows faster, not only windows of course though, it makes the computer itself seem 150% faster in my case.. i went from a Western Digital 2 GB about a year ago as my primary HD! I put in the Fireball and was literally BLOWN AWAY! and I can say the HD's were setup EXACTLY the same because I used Norton Ghost to clone my old HD when I was installing the Quantum. When windows first booted up ( the very 1st time ) I almost pissed my pants, it was INFINITELY faster.. then again it was QUITE an increase in HD... but it does answer your question, it was pretty near twice as fast...