At bare minimum you would need to get an IR (USB or serial )receiver and drivers. I have seen Msofts MCE IR receivers on eBay. Logitech has the MCE listed in their database so your 659 could/ should emulate it. Msoft, Streamzap and others offer remotes and IR receivers as well - most are again in Logitech db. However, I'm not sure what functionality you might lose or gain by not using the ATI control for your HTPC.