The UNIX/ LINUX way is:

  • always BIOS time = UTC

With Debian I use the crontab:
Code:
40      10,15,20        * * *   /usr/sbin/ntpdate -v de.pool.ntp.org; /sbin/hwclock -u --systohc
With dual boot Windows installation you have to register:
Code:
Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\↲
    Services\W32Time\TimeProviders\NtpClient]
"SpecialPollInterval"=dword:00000e10

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\↲
    CurrentVersion\DateTime\Servers]
@="1"
"1"="de.pool.ntp.org"
"2"="time.nist.gov"

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\↲
    TimeZoneInformation]
"RealTimeIsUniversal"=dword:00000001