Second HDTV Signal Delayed?

I have a GeForce 9600GT video card in my PC with two DVI outs. The first is running a DVI to HDMI cable out to my Sony 32 LCD HDTV that sits on my desk that I use for my monitor. It works great.

I recently ran a second cable to my 60' LED Vizio HDTV on my wall just to have an extra large screen for internet and gaming. I used an HDMI cable but this time I had to use a DVI-HDMI adapter on the second port of the video card. I also have Windows 7 set to "Duplicate These Displays"

THE PROBLEM:

There seems to be about a half second delay on the LED HDTV thats connected via the DVI-HDMI adapter. That may not seem like much but when when you need to move the mouse quickly or time a certain button press exactly, it can be an eternity!

Any idea what causes this since my other HDTV that I use for my monitor does not have this problem. Could it be the adapter?

 

Anyone with video experience have any thoughts on this issue?