Hello,

I have ABIT KT7A mainboard with 1GHz AMD Athlon processor.
On the startup, the computer says it's 750MHz and displays a message "CPU checksum error. Defaults loaded."
I go to BIOS and change the settings in SOFT MENU III required for my CPU. Then I save and exit.
The computer won't start at all.

I followed the instructions described in the user manual to clear CMOS. Computer starts again as for the first time saying it's 750MHz and "checksum error".
OK, I press F1 to continue. Windows starts fine and everything works.
If I restart computer I've got "CPU is unworkable message. Check SOFT MENU III settings". If I press F1 to continue Windows starts and everything works fine. Of course, it's possible to live with these message displayed and pressing F1 every time. But does 750MHz message mean that the processor doesn't work at it's full speed?

I've flashed BIOS with the latest version but the behaviour keeps being the same. I can't change anything in BIOS - computer refuses to start even if I change nothing in BIOS, just press F10 to save and exit. It can start again (with "CPU is unworkable" message) only if I quit without saving.

How can I make the better performance from my processor and mainboard?

Thanks in advance,
Max

7.5 x 100 = 750

7.5 x 133 = 997.50

Therefore you may have a 133fsb Athlon and there is probably a jumper on the MoBo to change the FSB setting, suggest you find out what CPU you actually have and read the MoBo manual.

http://www.cpu-world.com/info/id/AM...

http://en.wikipedia.org/wiki/List_o...

Thank you for replying, dosser.

I took my settings for processor from here:
http://www.hwspirit.com/tools.php?m...

The FSB of the MoBo is changed in BIOS.

Do you mean the processor will start only if I enter 997.5 value?

I tried the processor on another board and it works fine as it should.
So it must be KT7A MoBo which doesn't want to provide 133Mhz host bus speed. Is it a physical damage or there's something I should switch/turn on? I think the cause can be inside one of the chips? Can it be so? Should I through away the board?

Thank you