USB 2.0 Controller Performance

Low performance with High-Speed USB devices used to be a serious bottleneck of previous South Bridges from ATI. This was actually one of the main reasons why the mainboard makers were eager to replace the ATI?s own South Bridge with the ULi?s. Now that Nvidia owns ULi, ATI can only count on themselves. Let?s see what has happened to the USB 2.0 bus speed in the new ATI SB600 South Bridge. We will also check the bus speed provided by the new Nvidia MCP ?MCP55XE.

We used an external Maxtor OneTouch 250GB hard disk drive to tests the practical bandwidth of the USB 2.0 bus.

As we see, ATI managed to resolve the issues with the USB 2.0 performance. The USB 2.0 controller in SB600 South Bridge not only supports more USB ports, but is also working much faster having finally caught up with the performance rates of other controllers. The only remaining issue is relatively high CPU utilization when USB 2.0 bus is loaded heavily, however, it is not very noticeable during work in real applications.