okay for today I am testing a sans digital unit towerstor ts1UT it has an esata or a usb2 it runs for 30 bucks or so links; http://www.sansdigital.com/towerstor/ts1ut.html http://www.newegg.com/Product/Product.aspx?Item=N82E16816111110&Tpk=ts1ut this is the esata card low cost and boots http://cgi.ebay.com/ws/eBayISAPI.dl...GInUXbH0k0DbpuSId8%3D&viewitem=#ht_5021wt_851 first test is the 3tb drive seen with 1 3tb partition yes next test is writing 0's it starts out writing 0's at 95 MB/s Now you say that is slow your hdd should do 120 to 125 MB/s yes that is true. The jmb360 esata card is slow but it boots. I believe that when I test the sans digital case with my seritek that does not boot I will get 120-125 speed. Still if the jmb360 pci e card which is under 20 bucks and the sans digital tower 1bay which is 30 bucks do most everything at 95MB/s it would be not to bad at all for a 3tb external that should be bootable. This is why having an esata jack as stock for an iMac is really needed. You can just move the 3tb hdd from iMac to iMac. So far I have written 50gb since I started typing this. I am going to let it do the whole drive it will be slow but I want a good heat test since this enclosure is fanless. After the 0 overwrite I will clone an osx to it and test it for bootablity (is that a word?) I know the low cost esata JMB360 chip boots and runs systems around 100mb/s so for a 1 drive external it is nicer then a fw800 which is lucky to run 70MB/s. Not sure if it will so it with a 3tb drive but it would be nice to know. the screen shots below have info showing the hdd is seen and the speed of the 0 over write. I have a question for you mac'ers cause I do not know the answer. the 3tb hdd is shown in yellow like it is firewire or usb but the yellow icon is empty. it is an esata via pci e card my other one from seritek has a different icon it looks like a hdd case with 4 slots. so i guess a designer can make his disc icon look like whatever they want to. Am I right in this idea? A quick update I have been writing zeros for about 45 minutes around 340gb so far. The hdd case is cool around 85 f my house is about 76 f. I will wait and see what happens to the temp. Also the hdd is burning at 91MB/s a drop from 95MB/s at the start. At the rate of these speeds this will not finish until this evening but that's okay I really want to get a good idea of how hot this will get. Burning 3tb 0's is a good way to know.