Windows 7 Internet time is WRONG - it is ASYNCHRONOUS!

The discrepancies you are describing are unknown to me. The Windows operating system, Mac OS, and Linux all use Network Time Protocol. Microsoft's implementation of Network Time Protocol is handled through the Windows Time service. Accordingly, this service "Maintains date and time synchronization on all clients and servers in the network. If this service is stopped, date and time synchronization will be unavailable. If this service is disabled, any services that explicitly depend on it will fail to start."

Time between multiple computers can be entirely forced into synchronization using group policy options. In Windows 7 Professional and greater editions, you can explore some of the local options available in overriding the default Windows Time settings by going to Start -> Search -> gpedit.msc

This will allow you to access the local computer's Group Policy settings. Under this area, you can navigate to Computer Configuration -> Administrative Templates -> Windows Time Service

Under Global Configuration you can edit the clock discipline parameters. You can further configure NTP servers and synchronize multiple systems to one NTP server using Group Policy on a domain controller in Windows Server. When multiple Windows client systems are connected to a single domain controller to adjust, calibrate, and completely modify all NTP time settings.

Remember that Windows Time is designed to comply with the Network Time Protocol (NTP). This protocol has been around for a very long time, and is used by nearly every type of computer system that has network connectivity. Many SmartPhones and networked alarm clocks also rely on this technology. If Microsoft's time.windows.com appears to be giving you a wrong indicator, there are enormous lists of public NTP servers around the world, which can be found using search engines. These include NTP servers that are aligned to atomic clocks in different regions of the world.