Wireless network card performance

I am running FC4:
Linux maincomp 2.6.13-1.1532_FC4smp

I recently changed the OS from windows XP, and have a feeling that for some reason my wireless network card is slower on Fedora Core 4. The Belkin PCI 802.11b card was automatically detected and configured by FC4 when I installed the OS, but downloads from the Internet seem to be much slower. The wireless radio shows an excellent connection. The only hint that I get is the output from iwconfig:

eth1      IEEE 802.11b  ESSID:"something"  Nickname:"Prism  I"
          Mode:Managed  Frequency:2.457 GHz  Access Point: 00:09:5B:71:45:34
          Bit Rate:11 Mb/s   Sensitivity:1/3
          Retry min limit:8   RTS thr:off   Fragment thr:off
          Encryption key:off
          Power Management:off
          Link Quality=74/92  Signal level=-36 dBm  Noise level=-149 dBm
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:1454  Invalid misc:0   Missed beacon:0

The "Tx excessive retries:1454" worries me a bit. I wonder why that is. Is there anything different I should be doing? Thanks in advance.

Edit to add: transfers within my own network to the computer max out at about 170KB/s.