I will divide this answer in two parts.

1. If you will not format your PC for a longtime then surely you gonna face some slowedown issue. This is because users always install something small or big apps and that tends slow down PC start up. Some of the apps that cause slowdowns are : Steam, Garena, Adobe updater (AAM updater), Antivirus, there are some viruses which cant see in task manager but consumes your CPU alot, Chrome apps.
2. I know many people will not agree with my second point but truth is truth. Kaspersky is the worst thing you can have on your PC. Never ever installany antivirus on your PC ( Specially- McAfee, Avast, Kaspersky, Quickheal, Norton). Antivirus destroy your PC. If you know basic of using a PC then you will never need any antivirus. You just need one software and that is Microsoft Security Essential on windows 7 and Windows defender on Windows 10(Comes pre intsalled). Thats it. I REPEAT, DO NOT INSTALL ANY ANTIVIRUS . DOESN’T MATTER WHETHER IT HARMS YOUR PC OR NOT JUST DON’T INSTALL.PLEASE.

HOW YOU GONNA SPEEDUP?

The only possible answer here is to format you PC. Also, try uninstalling some apps and games that are not important for you. Remove useless chrome and firefox extension. You might see some difference.

THANK YOU.