Prob with resolution of monitor

[cyrux]

Today at my friend's place he had a prob. He has an Acer LCD monitor . His h/w conifg is p4 2.66 Ghz
He was playing around with the resolution of his monitor. His original res. was 1024x768 . He increased it to a higher resolution when the icons became smller. Then again he increased the resolution of his monitor to which the monitor when in stand by mode (very fast changing green and yellow light)
When the computer is restared the windows loading screeen is lhown and then after few seconds instead of getting in XP the monitor goes in the same standby mode.When i try to start the comp. in safe mode with command pronpt the drivers get loaded and hang up while loading the file called mpu.sys

So i took a windows XP cd along with me and booted the system and then reapired the current version of XP from the CD itself. After 20 miins XP started with 640x480 res. and after loading up an icon in task bar which read " found new h/w" and then it said "the current h/w is installed but may not work properly until the system is restarted". I ignored this message and tried to change my video mode to normal from the current 640 res. but then the video modes were not being displayed. here again a menu popped up to restart my system to
see the effects of the new h/w installed (which i guess is monitor) . So when i clicked "ok" the ystem restarted and the wondows xp loading up screen appeared and the same prob persisted. The monitor went into standby.

What i feel is that as the monitor gets recognised by the system it automatically enters into a resolution which is not supported by the system so the monitor enters stand by mode although its set on auto mode.
Note that when i check settings from monitor the resolution is set at 640x480 and horizontal refresh rate is 31hz and vertical is 60hz.

Has any body experienced such prob before and can help me out of present situation . Would formatting the system help . Is formatting necessary ??/

P.S How do i load up that screeen on system which asks me the options of how to boot up like
1) Noraml
2)Safe mode
3)Safe mode with command prompt
etc etc

[rajas700]

U better go with the option of Last Know Good configuration.By pressing F8.And in that u can adjust the screen resolution i exprience the same problem long ago......And before doing this just uninstall the graphics driver (Do these in safe mode by pressing F8 in startup)and the reinstall the driver after adusting the screen resolution in last know good configuration mode.