Great info, thank you. I am probably going to wait until the Bolt arrives and see how loud it is, then decide whether to upgrade the fan. I will have to open it up anyhow to install the new HD, so I admit I'm a bit torn, I might break down and order the fan ahead of time, so I could do everything at once. But if opening the case isn't too bad, I'd prefer to see how it sounds, first. I suppose I could leave the case not fully attached, between installing the HD, and upgrading the fan, if required. I wonder if raising the case a bit further off the shelf (like by putting something under each side of the case) might help a bit with cooling. Edit: Ehh, just ordered the XS-2 fan. If it's quieter, and also keeps things cooler, that seems worth doing, for $10.