Why does my cursor speed slow down when my system is under intense network usage?

On some occasions of computer usage, my mouse acts very strangely. Whenever my computer is under intense network usage (i.e. watching an online video, downloading an application, patching a video game), my mouse cursor slows down, and sometimes gets to the point of being completely unresponsive.

No matter how high I place the cursor speed, my cursor refuses to act normally. It travels very slow, sometimes not moving at all, and sometimes moving in short bursts. My left and right click functions might not function and as does my scroll wheel. However, my keyboard works perfectly and is just as responsive as it was before.

Whenever these intense network using instances are closed, the mouse nearly instantly returns to a normal, functioning state.

Incase some hardware & software are needed, I can supply a few:

Hardware

• i7-4770k @ 4.5GHz OC from 3.5Ghz
• 32.0GB (4x8GB) RAM @ 1.6GHz OC from 1.3GHz DDR3
• daskeyboard Model S Wired Mechanical Keyboard w/ MX Brown Switch
• Cyborg R.A.T. 9 Wireless Mouse @ 6400 DPI

Software

• Windows 7 Ultimate Service Pack 1

Some Applications that induce this behaviour

• Google Chrome, Firefox, and Internet Explorer streaming internet video from YouTube
• Steam when patching various games

Solution 1:

It's most likely one of or a combination of rendering lag, which would be your graphics card/GPU bouncing between the mouse and everything else, or poor wireless connection to your mouse. If your mouse requires any software beyond basic drivers to operate, that software may be throttled by running other intense software. I know Steam can be pretty intensive, and the same for your browsers, especially if you're streaming HD or have too many tabs/windows open.

Solution 2:

Are you connected via WiFi when you experience the slowdowns of the mouse cursor? If so, it would be that both your wireless mouse and WiFi are using the 2.4GHz frquency. When your computer is utilizing high amounts of network traffic, it could cause the WiFi transmitter to be emitting more signals than usual (rightfully so), thus causing interference with the wireless mouse communications.

Try connecting to a wired connection if you are not already, and turn off WiFi (Windows will still use WiFi if you are connected to both at the same time). Alternatively, try using a wired mouse and see if that helps.

I've experienced this issue on two completely different laptops years apart, one which was Mac with a Core 2 Duo and the other Windows with a Core i7, so I doubt it is a software or driver issue.