SharePoint Server 2013 - very slow in loading pages (frontend)

Hello, I have a problem.

I have install a SharePoint Server 2013 Enterprise. The enviroment:

1. Web-Front-End Server with 4 Core, 12 GB RAM, SSD (WS2012, SharePoint 2013 RTM + CU March 2013)

2. Backend SQL Server 2012 with 3 Core, 10 GB RAM, SSD (WS2012 + last Update)

The central administration page works fine, how sharepoint 2010.

The problem, when I access a web application, every site (main site, sub site, document library, ...), every action need 2 - 3 seconds. On the right side is the popup information "is in work ...". No CPU or SSD/HDD usage.

I have found the problem in the internet, but no solutions work.

http://social.technet.microsoft.com/Forums/en-US/sharepointitpropreview/thread/16cebde9-da9e-43a2-9d6a-656693ab65c5

http://social.technet.microsoft.com/wiki/contents/articles/14287.sharepoint-2013-how-to-improve-speed-on-sharepoint-2013-en-us.aspx

1. I have set the maximum of the noderunner from 0 to 128 (no solution)

2. I have disable the two search services (no solution)

3. I have export and import the trusted root certificate for the 3 certificates for sharepoint, no solution.

I need help. Does anyone know theproblem?