I reluantly upgraded to Windows 8.1 because AMD dropped support for windows 8. The truth is windows 8 is better for gaming than 8.1. I also started experiencing the pagefile spike when playing games in fullscreen. I've tried everything, even installed my original drivers but it keeps re-occurring. Before 8.1 my Windows Experience Index was 7.2, 7.9, 6.7, 6.7, 5.9 (6.7s being for gaming) but now its 7.4, 7.5, 5.9, 5.7, 5.9. My system specs are
Intel Core i5-3230M
8GB RAM
Radeon HD 7670M + Intel HD 4000
Windows 8.1
I tried the latests windows update and Intel graphics driver update but to no avail. Windows 8.1 is a mess. And I don't advise any gamer to upgrade cos its not worth the headache.
Intel should release a driver update to minimize this frustrating issue.
The only temporary solution is to run the game on the same resolution as ur desktop. Although it doesn't work for all games cos I still experience it even after doing that when playing Assassins Creed 3.
I hope this is resolved fast cos its six months now and still no solution