The problem is most likely your router configuration. The 1703 adapter will conform to the router standards. So, if you have wireless b or g devices on your network, the router has to slow the adapter, which complies by dropping down to 72.2 mbps. If your network was all wireless n and your router was capable, the 1703 will run very quickly. My own test (wireless n only) was 225 mbps. In a mixed environment with wireless g devices, it drops to 72.2. You need to set your router to receive up to 300 mbps and also disable 20/40hz coexistence, which is designed to slow the wireless down when there are neighboring wireless systems present. In your PC's device manager, under network adapters, you can check the 1703's advanced properties 802.11 n bandwidth to make sure it is set 20Hz/40Hz auto. The Dell Wireless 1703 802.11b/g/n will then run at n speeds. Just remember that if you want to add a wireless b or g device, the router will have to slow the adapter down to accommodate them. Your security settings can also affect performance. I believe WPA2-PSK [AES] is optimal.
Best of luck!