Trying to connect handheld GPS to PC via this cable. OEM is serial, PC doesn't have a serial port.  Ive looked everywhere for a driver for this cable (Serial to USB). Ive FOUND other manufacturers but not Dynex. Could they possibly be compatible. Will it hurt to TRY. Any help will be appreciated.I have the same adapter and the drivers are available at www.dynexproducts.com under "Customer Support".  I've been trying to get an external modem to work with Windows 7 using the serial/USB adapter but the drivers on the website will not work with that OS.  If anyone has any suggestions for that please let me know.  thanks! Dynex doesnt have an update.  I also have the Dynex DX-UBDB9 cable, and found the following driver that
works like a charm in Windows7 (even at 64 bit).

The driver you NEED is this one:
PL2303_Prolific_DriverInstaller_10311.z ip

Download it at this site:
prolific.com.tw


Remember to unplug anything plugged into your USB ports, install the software, reboot the computer, plug in
the USB-Serial Cable (but disconnect it from what it is attached too, ie, a GPS unit), and windows7 should recognize it.

then plug in your GPS, or what ever into the cable and you should be good to go.

Yes thanks Ryder.. It does now recognize the USB to serial cable however it doesnt recognize the external modem that I have.  It's a US ROBOTICS 56K external, Model 5686.  It will not pick up that the device is there at all.  I've tested it on another computer serial port directly and it works fine.  I want to confirm that ryder2008's RECOMMENDATION is correct.  The drivers from "prolific" support the Dynex device under Windows 7 x 64, and I was able to download waypoints to my old SportTrak Pro.

The only downside is that I no longer have an excuse to get a new GPSr.