@jayk: Sorry for reviving the old thread, but I thought I should say this. You aren't *using the computer* to play the NES. It's not even touching the computer.

What you meant to ask, and what no one who replied seemed to understand, is;

"Can I plug this NES thing into my Monitor using the HDMI port?"

The answer is YES. Of course you can! As long as the NES has an HDMI-Out and your monitor has an HDMI-In it will work exactly like a television. But just because it's plugged into your monitor, don't expect your mouse and keyboard to be detected by the console. Thinking that would just be silly...