The following measures can help you make your hard drive run faster:
(1) USB 1.1 must upgrade to usb2.0. Both desktop and notebook have usb2.0 card. You should not get petty when purchasing card.
(2) The hard disk models should new when you purchase one, the general production of the external hard disk since 2002 have the capability to go 15M / s.

(3) USB interface: First of all power should be enough. Control chip with NEC or INTEL ICH4 / 5 South Bridge is better, followed by the ALI, VIA. However, these chips actually have the capacity to run 15M / S, the pcb board design and workmanship is also important.

(4) The box you choosed should be a better one. The bridge chip NEC rarely used in the hard disk box, generally used in the CD-ROM, NEC also very good, and can be compared to ISD300. In fact GL811 also went to the level of 18M / s, as the same principle of the adapter, the speed of external hard disk decided to pcb design and workmanship. Picking expensive Cards and boxes to buy is certainly not wrong.

(5) The local hard disk also must run fast enough.

(6) USB 1.1 speed is 1M / s, usb2.0 passing level is 10M / s, if less than 10M / s, then the laptop hard drives, boxes, interface, the local hard disk at least a bottleneck. I used the ASUS Intel 845PE motherboard, dual interface box Proterozoic (ISD300), Hitachi 80GN hard disk, local hard disk ST7200.7, speed can reach 22M / s, the same platform, using GL811 box also reached to 18M / s. 22M / s hard drive transfer rates have been almost the limit, and it seems this time the bandwidth usb2.0 not feed. Poor usb card can only reach to 4M / s.