Have Smartboard working all fine with 11.3 on Windows 8 on older 'black' 500 series smartboard. Just needed to manually install driver for the old serial to usb cable on these which are not supported anymore by smart. Got them from pnpdriver folder from older laptop still running version 10. (Pnpdrivers64 for 64 bit) That's within program files/smarttechnologies folders. Just direct device manager there. Took me a few days of trying different versions and thinking was going to need new boards but all working tip top green light now. Hope this helps someone.
Also applies to W8, this has worked for our x64 W8 clients.
I'm trying to get my SB540 to work with Windows 8 (per Trigster79's post) but haven't got the older version of the drivers. Can anyone help?
OK, I found the v10 drivers here and this enabled Windows 8 to recognise the Smartboard using Trigster79's method.
I also got the board to work using the old serial cable connected via a female-to-female gender changer and a Prolific USB-Serial cable. The power needs to be connected via the PS2 keyboard connector and a USB adapter. Messy (and uses 2xUSB ports), but might help if you've only got the old serial cable.