My USB2.0 Hard drives dont seem to be running very quicky. Its a WD Blue 320Gb drive with 16Mb cache in a USB2.0 housing. Ran HDTune on one of them and get this result :

This is in the rig in my sig, all chipset drivers are installed. I have another 200gb IDE drive in an external enclosure and get the same results, max 30Mb/s, min 28Mb/s

This is in the rig in my sig, all chipset drivers are installed. I have another 200gb IDE drive in an external enclosure and get the same results, max 30Mb/s, min 28Mb/s