Here it is my problem!
My video settings must have been changed or something and now when I start my machine, it shows the BIOS and the WinXP splash screen but after that it goes black and my monitor flashes up the message
"75K / 120Hz Frequency is out of range"

PLease help me on finding a solution to fix my machine.
Thanks in advance

http://support.microsoft.com/?scid=kb;en-us;315614

Follow the advice there

thanks for your kind support but the problem is that i can't access the windows on this machine.
any other suggestion?

I assume that since the OS starts the problem is a momentary "frequency out of range" during startup, primarily when the system transfers from hardware start to the os level. This happens when windows monitor drivers are old or the monitor frequency set to the wrong value from within Windows display control panel. Try checking the value under the advanced monitor properties area.
It's in the display control panel, under [settings] (advanced) [Monitor].
You will look for "screen refresh rate" . Be sure this value is set between the values called out in the message you received.

A second question is - What Internet security or Antivirus software are you using. If it is norton, disable the "load auto protect during boot" (advanced properties), as this can also cause a similar message.

I have had similar messages, and this took care of that problem. btw [ ] is a tab, and
( ) is a switch or button.