Thank you very much ac3mark for your help .
My PC is an ACER, (Model: Aspire M1100)
When I switch on the pc the power is on however the pc does not immediately boot up. I have to leave the power on for several hours, switch the pc back off and swith it on again and then it eventually boots up.
Once it boots it goes straight to a screen which displays the following:
phoenix - awardBIOS v6pg, an energy star Ally
Copyright (C) 1984-2007, Phonix Technologies, LTD
This BIOS is exclusively for Acer only <R01-A1>
Main Processor: AND Athlon(tm) 64 x2 Dual Core Processor 4000+
Memory Testing:786432k OK +256m shared memory
IDE Channel 0 Master : HL-DT-ST DVD-RW_CSA-H41N RA00
IDE Channel Slave : None
IDE Channel 2 Master : Hitachi HDS721616PLA388 P22OAB3A
IDE Channel 2 Slave : None
IDE Channel 3 Master : None
IDE Channel 3 Slave : None
CMOS checksum error - Defaults loaded
press F1 TO CONTINUE, DEL to enter SETUP
06/25/2007 - RS690 -SB680 - 6A669FK8C -00
do you know what this issue is ?