I have a Dell Inspiron 1520 laptop and am wanting to add/upgrade high speed transfer hardware
(mainly for an external hard drive backup device - I have yet to pick out or buy)...
Would a usb 3.0 add-on card be best/fastest/ most cost effective route?
Will also be building a desktop pc, would like to add dedicated hard drive to build and work laptop into back up strategy from it.
Looking for advice and/or suggestions pointing toward specific hardware (best mfr/model,price)
I don't know if that one has a PC Card (formerly PCMCIA), but that would be about your only option if you want to add a USB3 socket.
You could check if your laptop already has an eSATA port - quite a few do. eSATA is almost as fast as USB3, and plenty fast enough for an external hard disk (much faster than USB2!) - using eSATA might be easier.
There is another option - you could put your backup into a NAS (network attached storage) box, and add it to your network. Then both the desktop and laptop could see it at the same time. The NAS would be more expensive than an external hard drive, but more flexible. And your laptop already has a network connection...