computer?

Make sure that you don't make it do to much at the same time.

Take a look at what is actually running, especially stuff that start automatically with Windows.
Disable any auto-starting applications that you don't really need. Make sure that any application "accelerators" are disabled. They are utterly useless and only make your computer start slower.
Using the task manager to kill tasks is good, but those will come back with your next restart. It can't set anything not to start.

Delete any useless files, like old temporary files. CCleaner if a great application to do exactly that. To be run monthly.
CCleaner can also be used to disable auto-starting applications.
A disk that is to full gets slower as it takes more time to locate a free spot when you need to write to it. Also, it can take more time to locate the file that you want to read as the number of files in a folder increase.
Also, a clean drive takes less time to scan for virus/malwares and defragment.

Defragment your conventional drives, but never defragment any SSDs.
Defragmentation should also be done monthly, but ONLY for conventional drives.

Make sure that there are no malware running. Get and use some reputable anti-virus. Microsoft offers a good one, and you can also use one of AVG, Avira or Avast. All are available for free. Don't get the trial versions.
You must NOT have more that a single antivirus active in the background at any time. If you have more than one installed, make sure that only one is set to protect you in real time, and any other must be set to run only on request or manually.
Another pretty good one is Malewarebytes. It's free version is made to be used manually.

Get and install Spybot to get rid of some other, non-viral, nasties. Get the free version.

Be sure to get them as up to date as possible, and update the definitions daily. Any auto update must be turned ON! That's the default setting that must not be changed.
An anti virus set to be run only on request also must be updated manually before each use.

Uninstall any old applications that you no longer use or need. They take disk space and may start, now useless, processes and tasks.

Electro
May 2016

You can't make it faster - it runs now as fast as it ever did.

What you probably notice is a slow response from the machine because it's doing too many things.

Rogue software gets itself an entry in the start-up list - lots of it over time and it runs in the background slowing down response time.

Use Task Manager to prune your start-up list - mine has all the entries deselected.

Also in Task Manager look at Processes and see which process might be using all the machine resources (% CPU) - one or two percent is OK for any utility but investigate anything over 10% and check it out - you can Kill a process - end process.

At the moment with just Google Chrome and Task Manager running my own CPU % is never greater than 5.


Good Luck...
May 2016