Do you know your core temps when you were having the rebooting problems? My system appears much more stable now that I backed off my folding CPU limit to 90% instead of 100%.Bebop I had problems with my computer rebooting 1-2 times a day when i was running a 3.2Ghz Pentium D with This cooler (and Yes it's kinda big) but when I upgraded to a Q6600 i decided to get This cooler (and yes it's TWICE the size of the other one) I haven't had any more problems with cooling or rebooting since I've upgraded. so if it will fit I'd suggest the second over the first.
P.S. I have all of it in This Case
I'd still like to try the Artic Cooler at $31 instead of the Thermaltake $67 (with shipping, and only 1 year warranty). I blew my budget already on the 9800GTX video card, so I've got to curb the spending! Thanks for the tip, glad you aren't ahving any more issues. I'm going to hold of on OC'ing my CPU until after I get my system stable with the new video card.