I got same problem, the entire system went slow and lagging after update to 8.1.

The touch can not continue and break from time to time drag item.

I have a similar problem, after 8.1 upgrade

On ASUS CM6340 desktop with CORE I5 and 10 GIGS RAM

Periodically the task called SYSTEM goes into a controlled compute bound loop at 30%CPU utilization spread over all 4 cores. This results in very sluggish performance. As I try to narrow down the problem I find more and more things that are implicated. I can cause it at will by running Microsoft solitaire collection free cell and sometimes just the Microsoft solitaire umbrella program causes it.

I have also seen it sometimes when accessing a youtube video. Other unknown things seem to cause it.

It always boots without the problem but occurs some time later or as soon as I run freecell.

 I have been searching for other reports via google but have not found anything,

Same happened to me as well. I was hoping that installing newer video drivers would help, but it only helped a little.  Did anyone find anything to help mitigate the slowness?

I've spent quite some time on Google, but can't find anything.

I didn't write this earlier, but the touch screen is much less responsive now too, particularly with the edge swipes.

I can't seem to find a way of going back to Windows 8, so I'm going to reinstall Windows. Has anyone got a better idea?

Thanks for your help. 

I have the exact same problems. The system has become sluggish and unresponsive. I have tried updating any out of date drivers, but nothing helps.

Same problem here, plus the attached mouse is lagging too, especially at disk operations(???)

Watch out, W700 owners, there are many driver update on the Acer.com!

Yeah before 8.1 my w700 was running very smoothly on both balanced and powersaver mode. Now it lags heavily on both....web browsers lag, ive tried them all and the plugged in mouse is slow and unresponsive.

The only fix that has helped me manage to get by this problem is to plug it in, when it is attached to power it doesn't lag at all and runs like it should, hopefully microsoft fix this issue soon!

the updated drivers didn't help much, they got rid of some of the lag but its still not as smooth as it was before 8.1. The desktop applications work fine now, the main issue is the web browser, during loading times..the mouse is extremely slow during this...

same thing happen to me...it is very annoying...and i cant stand that, the tablet is unusble. i am going to reinstall win8....the worst upgrade ever