Well, I did it to myself. I bragged the other day that early 2006 20" Intel CD iMac running 10.4.11 Tiger had been running for three+ years without me ever having to do anything to it. Now I am forced to admit that it has begun to get a little sluggish. Basically, it keeps running out of memory, ( 1 GB installed ). I've ordered a memory upgrade to 2 GB, but, I've also noticed that when I open the Activity Monitor, there seems to be a lot more processes running than when the machine was new, even after restart. This includes a process called "kernel_task" which is sucking up 10% of memory at all times. I really think I need to re-install the OS to clean it up, what do you think? Also, if I do re-install, what would be the best way to do it? Would Archive and install do the trick, or do I need to reformat the HD and start new? If I do a reformat, what files will I need to copy so I don't lose my documents, apps, pics, and iTunes library? ( I have a 500 GB Maxtor external I can copy stuff to). I will be upgrading to Snow leopard, somewhere around 10.6.3, but don't know if I want to wait that long I've attached a couple of pics of the Activity Monitor, top half and bottom half.