Did you find out sometimes when you updated your windows then it  was running slower than before? Or, in worse case it was crashed after updates? Well, it happens sometimes. Why?

That is because the window update has impacts on the existing drivers in your computer;  It is a compatible issue between the hardware drivers and the Operating System. Specially, the drivers of video card and the mainboard that installed in your computer are programmed to work perfectly on the environment of previous version of Windows. It is not for the new Window Operating System after updated so when the new updated OS comes in to the place it could either cause the slowness or crash the display driver after the updates.

Most experienced windows users, usually do not auto update the windows OS after they installed the hardware drivers (eg. display card driver).

Keep them in mind:

<1> We can get the new driver from the manufacture's website. However, the hardware drivers' date must be older than the date of Windows Updates. 

<2> Only update the video/mother board drivers on the manufacture's websites - It is fully tested and it is faster. Do not get the drivers on the Microsoft Windows Updates website - It is likely slow and problematic.

<3> Be aware of third party software that are installed in your PC. Some of them could be very bad. 

Here is an example:

If the video/graphic card driver was released on "1/1/2015" then should not install any windows updates which are released after that date.

If the security issue is a concern then a firewall should be installed. Customers may not very concern about the unseen security issues but they definitely will not be happy if they see the blue screen after the updating. :)