The Micro$ofties stuffed Windows 8 chock a block full of crapware, programs that suck up RAM and CPU time but don't actually do anything for you. Every so often I go out on a crapware hunt, and I always find something. Today I scored three kills. First off is a program "DasHost.exe". It is supposed to alert you to incoming email, sometimes. My email client, Thunderbird, has been successfully detecting incoming email for years with out it. After a net check, the consensus of opinion was "worthless", so I went after it. It's a service. Services are little (and some times not so little) programs that Windows runs behind your back. They all suck up precious RAM, and hog CPU time. They show up in Task Manager as processes and there is a special Windows program to manage them. Go to Control Panel. Pick Admin. Tools. Pick "Services". Find "Device Association Service. First STOP the Device Association Service. This shuts down the copy running in RAM at that moment. Then hit "properties" and change the startup type to "disabled". That preventsWindows from starting it up on the next boot.
While you are in there, find service "Themes" and give it the same treatment. Themes suppores the fancy Aeroglass look in the display. It sucks up a lot of CPU time and I don't like the look, I prefer the standard old Windows look.
My last kill today was "Power2Go Gadget". This is not a Micro$oft program, and several websites called it useless. It is NOT a service, so you cannot zap it thru the Services program, like Dashost and Themes. I found it with Task Manager, and the Windows 8 Task Manager can stop it, and prevent it from reloading (disable it). I'll double check tomorrow to see if it stays dead, but it's stopped now.
For doing all this, laptop feels livelier, it can keep up with my typing now.
Be careful messing with services. Back in XP, there were a couple of services, Remote Job Entry for one, that were essential to Windows. If you disabled Remote Job Entry in XP, Windows would never boot again. The only fix was to reinstall Windows from scratch, a tedious task, especially if you lacked the install CD-ROM discs. I suspect the Micro$ofties have planted similar booby traps in Win 8, but I don't know what they are. So don't disable anything unless you are sure, or have searched the internet and found an authoritative site like Black Viper to say that you can disable it without a disaster.