Windows 8.1 is causing terrible mouse lag in a number of PC games, including Call of Duty, Metro 2033, Deus Ex, S.T.A.L.K.E.R.: Call of Pripyat and many more! Until the is resolved, don't upgrade to Windows 8.1!
Windows 8.1's new dpi scaling feature has put a polling limit in place for gaming mice of under 200 hz. Gaming mice with previous OS's, are capable of being polled up to 1000hz. This polling rate is available in most decent drivers, e.g selectable for mice from Razer and Logitech. If the polling is reduced, it brings in input lag into games.
- Right click the EXE of the game in question
- Go to properties
- Go to the compatibility tab
- Tick the box marked ‘run this program in compatibility mode for’ and select ‘Windows 8’
- Tick ‘disable scaling on high DPI settings’
- Tick ‘run this program as an administrator’