I'm sorry to hear that you are experiencing difficulties with the HDMI connection on your SyncMaster 2333HD.
It sounds like you may need service. Please contact Samsung Customer Service toll-free at 1-800-726-7864.
I have had this tv/monitor for a little while now and it serves its purpose as a second monitor well. The problem is that it no longer recognizes anything that i plug in either of the HDMI plugs. I've been using it for my Xbox 360S and one day it just stopped recognizing the xbox, or anything else for that matter. All it says is No Signal. So it sees that there is something attached to the other side of the HDMI cable, it's just not talking to anything anymore.