I am running Windows 7 and Ubuntu (dual-boot) on a Lenovo machine.
I recently installed the GNU/Linux distro. One or two days afterward, I noticed that the clock on the system tray was out of sync by about five hours. On a hunch, I checked the Services applet and saw that the Windows Time service was disabled. Naturally, I changed the setting to autorun or autostart with my administrative privilege.
That seemed to solve the problem temporarily. However, the next day the clock was out of sync again. When I checked services, it showed that Windows Time services was "stopped." By the way, the first time I noticed this problem I manually updated the time by going into the "time and date" settings. This would solve the problem only temporarily.
Interestingly, I have not had this problem with the Ubuntu partition, except today when I noticed the time was out of sync but it quickly re-synced itself a few seconds after logging into the desktop.
At this point, I am annoyed and worried that it might be something more serious. I also tried changing the Internet time server without success (i.e. the clock still keeps getting out of sync by several hours). I only have two other hypothesis to test. The first is that the BIOS battery is dying —this is a laptop, though, so I do not know how the motherboard is set up or whether it even has a BIOS battery or not.
The second hypothesis is malware. I also downgraded my AV software recently. Incidentally, I had some problems with the Windows Firewall not working after that, but it is fixed now.
Any helpful advice would be appreciated.