Computer randomly shuts down help plz!! please!

if anyone, ANYONE! can help me, it will be VERY much appreciated.

System: 1.1g AMD Athlon,MSI k7t133 pro a, a gforce2 4\mx 400, 512mb ram, OS XP

As a gamer at heart I like my games to run...all the time.
I've had this problem which is on and off but very disturbing,
at times (varies per game) my joy bringing computer
....
.......JUST SHUTS DOWN , not even off. it seems as if its in suspend mode, everything is on HD light is perm on but reading no info. Screen goes off.... uhh hell 4 a gamer.

I've tried everything... updated detonator drivers, all the new Via drivers, even bios update.

I thought it may be my powersupply but only in games does this happen ARG!!. Also power supply is reading normal voltages when tested.

I even placed additional fans in the box and replaced my fan on chip for a more powerful one, thinking it may be overheating. PLEASE GOD HELP ME I'm GOING CRAZY.

So to anyone who may recognize the problem... I LOVE YOU.

thanks
Turbo

 

check this article here http://www.geforcefaq.com/faq.cgi#hw:gef:troub:blackout

If the card is running agp 4x try 2x, you should have an option in your bios to change the agp

 

The info on the sites and links thereafter helped a great deal.
Thank you so much !!
Turbo