My P4B will not boot. I am trying to install XP and all that comes up is "system intruded chassis opened or tampered before. Please check system. The installation is A-OK. what do I do. PLEASE!! Paul

Hello, you can download a manual here:

http://www.asus.com/Motherboards/Intel_Socket_775/P5PEVM/#download

Please select your windows version.
Select manual and click on global for download.
Unzip the file before installation.

And remove the cable on the mainboard for the contact on the chassis.
When that is done enter the bios and set the setting for the chassis intruder to off
Read about that in the manual.
The chassis intruder is used by admins to see if the case have been opened
when the case is opened the bios will block the system from booting until the setting in the bios
is set back to normal.

When you open the computer case, a switch is tripped and after the case has been closed and the computer boots up, you get this chassis intruded message.
To clear this message go to the BIOS configuration and then to the chassis intruder detect and then Reset this setting.

in your system there is small black push to on switch is there in cabinet press that or close the cabinet properly check cabinet switch connection also

This is a safety feature.
To turn off this feature open you're manual to page 1-15. Follow the instruction, item 2. Chassis intrusion connector (4-1 pin CHASSIS). If you need the manual download it from Asus; http://support.asus.com/download/download.aspx?SLanguage=en-us
At the time of this post Asus Global site is down for repair. Suggest you type, P4XP-X in the search window located in the upper right hand corner of the above link. Than click on:
P4XP-X related files for download

Cheers'
Mike

You need to check the chassis intrusion pin setting located on the motherboard. See page 1-30 (Number 11) in your manual.
You need to add a jumper as shown.
The system should no longer halt.

Cheers!
Mike

Your motherboard has a chassis intrusion detector. This just means that someone opened your computer case. Since you did this to change drives all you need to do is reset the detector and you'll be fine. You should have a setting in bios to reset the detector. Hope this helps.

There is a mechanical switch connector available to determine if someone has opened the chassis.

You can bypass this through the BIOS by entering the BIOS on bootup (DEL? message at bootup? F1?) then look for the system chassis intruder alarm and DISABLE

Another option is to find the pins that the switch is supposed to be connected to (documentation on the ASUS P4B motherboard) and jumper them.

You need to go into your BIOS and disable chassis intrusion detection. You can get into your BIOS usually by pressing either F!, F2, DEL, or F10 when the computer boots up. Check with your motherboard manual or look on the startup screen for the correct key.

plz disable the chassis open warning option in the bios.

hi, SInce u do not have a HDD u will need to boot up from cdrom, for that in the BIOS 2nd options,change the boot up sequence first to cdrom , second to any other disk.. let me know