Hi ,A couple of weeks back i started getting Checksum Error at boot,, so i fitted a new cr2032 Lithium Battery(duracell) on the board, old 1gb Celron , it's never gave me trouble before.. anyway that seemed to solve the problem… On sunday i booted and it went straight to bios, with the CPU Warning ,, Since you use a new CPU or reinstall CPU (WHICH I HAVEN'T ) system boots up at the cpu external freq of 66mhx to make sure system can enter setup menu bla bla bla ,, Once i reset to 1000 mhz ,hit f10 , then enter it's running again ,i just reset clock when the warning comes up… Pc runs fine till next day when i reboot,, then have to do it all again,not that it's a big problem,more annoying, i haven't rechecked the new battery but will , and then refit,, otherwise i'm a little bit lost as to why this is happening,or is the board on the way out,,, any ideas welcome,, thanks ,Snowy .. ps ,m/board is ASUS TUSL2-C , 815 CHIPSET.. <_<