How to change startup impact for program in windows 8? Is it possible? If I make low impact for all programs, windows will start faster? Is it has sense?
You can't arbitrarily change the startup impact for your programs by simply setting them to low impact. The impact is just a measure of how that program's actions are affecting the startup.
The easiest way to make the system start up faster is to remove high-impact programs from startup. You'll have to start them manually after the system boots up.
You can also see if you can change what the programs do on startup, to try and reduce the impact they have. This is highly dependent upon the program, though.
The impact is measured by the Windows Diagnostics Infrastructure service and can't be changed:
This blog post shows you the details how Windows detects the impact:
One method is to spread the startup programs across your drives.
In cases where I can't control the location of the install, I like to use symbolic links.
For example let's say I wanted to move the Google Update installer to a different drive. By default it's in %LocalAppData%\Google\Update
I'd move the folder to the other drive, maybe D:\Google\Update.
Then I'd use MKLINK to create the symlink: