A lot of players seems to have problems with fps drop after the 8/3 steam client release.
Cant confirm or deny keylogger/malware/webcam hack/wife beater in any of these files, so
use on your own risk.
Basically you roll back to the old steam client files:
1. Download the needed files here:
https://dl.dropboxusercontent.com/u/83131608/Steampre8-3files.7z
2. Quit steam;
3. go into your steam folder, and delete all the root files, but dont delete any of the folder and files inside these. They only folder that should be deleted is the "Package" directory.
Picture
4. Extract and copy all the files from the archive to the steam folder.
5. Now, disconnect the internet cable/network card.
6. Start steam, when it pop up and ask you if you want to "start in offline mode" or "retry", you now reconnect to the internet.
7. When you are connected to the internet, you click retry, and steam will start, running buillt "Feb 4 2016". Confirm this by clicking Help -> About steam.