Windows 7: Razer Deathadder Problem

Hi, I don't know if I'm in the correct section or I don't know if the people on this website can help me, but I'll ask anyway

Basically, I had a Razer DeathAdder with Windows 7.
I had the drivers installed and everything was fine.

Now the issue isn't the physical aspect of the deathadder, it's more when I'm in-game (Call of Duty 4) Previously I used, 900 Dpi, 1000Hz and 1 Sensitivity in-game.

I sold my friend the deathadder I had and I bought another one, but with this new deathadder (with the exact same settings ingame, in the drivers and in windows 7, my aim in game seems to be really shakey and inaccurate. and nowhere near like before, can anyone tell me if this is just a Placebo effect or if there could actually be a problem?

Borrow another mouse.
If the problem persists then it is the computer's fault.
If not; then it is the mouse that is broken.
OR
Try uninstalling the mouse from the device manager, reboot and get windows to detect it again. (re-install the mouse driver)

You could also try updating the firmware on the newer Deathadder plus uninstalling what drivers you had on and get the specific set for the (And i'm presuming here that it's a Respawn) new mouse.

The older Deathadder used a 3.0G Infrared sensor were as the newer one (Known as Respawn) is a 3.5G Infrared sensor.

I also went from the older Deathadder to the new one and found it twitcher but after updating driver's/firmware it's been fine ever since.

Good luck