I've said this many times,
all retail maxtor hd is ATA100 already long time ago,
amazon, staples, dell, etc all just use the info from the supplier,
the supplier hasn't updated the info.
when dell has 25% or 20% off, you could get this hd for around $102-108 shipped.
beware it's a quantum fireball plus AS inside,
if you don't like quantum hd, don't get this retail maxtor.
get oem/bare drive maxtor from other places.