[CentOS] system gets suspended automatically!

[Chandra]

Sorry for not writing very clearly. here are the details:

$ kernel -qa|grep kernel
kernel-PAE-2.6.18-53.el5

$ uname -a
Linux localhost.localdomain 2.6.18-53.el5PAE #1 SMP Mon Nov 12
02:55:09 EST 2007 i686 i686 i386 GNU/Linux

$ rpm -q centos-release
centos-release-5-1.0.el5.centos.1

Also, I checked that if I reboot the system without any external
attachment (i.e. no mouse, no keyboard, no monitor) and attach these
elements later, none of these are recognized. What I want is just a
network connected CPU to run the program. That's all. I can control
the program running on it using ssh from another machine. I would like
to add one more thing is this: when I log into a gui-session (gnome),
and run my program on a terminal there, it lasts for 1-2 days before
suspension. However, if I log into console-mode (no gui), it lasts
only for 4-5 hours before suspension. I again think it is entirely a
kernel problem. Would recompiling the kernel with some specific
options help?

Thanks for allocating your time!!