|It's the free space that's remaining on the partition Windows itself was installed on that's important. If there's not enough free space % left on that, Windows will run MUCH slower than it does when there's more than enough free space. |
What is the total size of that partition on your computer ?
If 2gb free space is a lot less than , say, 10% of the total size of the partition, you don't have enough free space on that partition.
".... i don't install any program which demanding high system and technical requirements....."
Programs that are installed but are not running don't require any system resources.