Replacing the CMOS battery should resolve this, when you have replaced it you will
need to go into the BIOS and re-set the time and date, save and then exit.
Try Tapping F8 on booting up to get into the BIOS, or possibly F1 or F2
The 2004 date will be the year of the default settings, regarding inspecting the psu
make sure all of the power leads from it are securely in the connections and as Digerati
said make sure the psu fan (or any other fan) is not clogged with dust.
Here are the keys to tap to get into the BIOS on the different Dell machines.
Dell 400 F3, F1
Dell 4400 F12
Dell Dimension® F2 or DEL
Dell Inspiron® F2
Dell Latitude Fn+F1 (while booted)
Dell Latitude F2 (on boot)
Dell Optiplex DEL
Dell Optiplex F2
Dell Precision™ F2
Edited by phillpower2, 29 August 2010 - 02:07 PM.