Well, the message is telling you that your BIOS clock is off and needs to be reset (manually) by you.
How to get into your computer's BIOS - http://www.cyberwalker.net/faqs/reinstall-...enter-BIOS.html
This can be caused by various things, the most notable being a failing CR2032 battery in the BIOS.
CMOS Battery. - http://www.geocities.com/micksmix2000/cmosbatt.html
When you go into the BIOS to reset the time, take note of the date reflected also. If it is wrong (in addition to the time), it might be change to simply replace the CMOS battery.
But try adjusting just the time first
While you are in the BIOS, also check to ensure that the drives you currently have installed...are reflected properly in the BIOS. Most BIOSes which are relatively new will adjust automatically for changed drives, but there are many in use (this system has one) which requires a manual adjustment.
Probably more info than you need but it may be of use: http://computer.howstuffworks.com/bios.htm/printable