How to identify USB 2.0 bandwidth

Is there a way to find the data speed used by existing usb 2.0 controller. I had attached a usb pcie card at my system and the specification of shows, that it will be around more than 12mbps of transfer speed. But when I had attached my network drive on that the data is very slow. I had a intranet website that lags when anyone start working on data processing. I had updated the drivers and also ensure that there is not other app using the nas storage. Can anyone provide some kind of device which can help me to calculate what is the data transfer speed of a port.

There is no tool for that. You can test that by copy pasting a bigger size of data. You can see the transfer ratio on the screen itself. If you are using Windows 7 then you can see the actual transfer rate. You can try this on different pc. USB transfer ratio is also affected if the usb ports does not get enough power. This power is limited via certain power aver utility in windows. Compared to regular controller on board, usb card offer you more speed. If you still find it slow update the drivers.

There is a small tool called as NetWorx. It is a bandwidth monitor software which is basically used to monitor lan data transfer bandwidth. I am not sure whether it can detect your usb but if you have a NAS drive, then simply copy a large file to your existing system. Check what speed it shows you. If the chart shows falling bandwidth then there are chances that the card is defective or there is some issue with the network policy. There can be restriction imposed on data bandwidth. You can also try different kind of data monitoring software which can be used for similar purpose.