9800gtx gaming problems pls help

Hey all,

Recently i decided to upgrade my computer so i could play some of the new games out there like call of duty modern warfare and crysis and all the other latest games out there at the moment. anyway the graphics card i decided to get was the (EN9800GTX+ Darknight) which i thought would serve me well and make my gaming nice and smooth.
however this is not the case i installed cod4 and my fps just freezes out of the blue it will drop to 20 fps from capped at 125fps. i dont know why this happens but its extremely annoying. i have tried heaps of things to fix this issue but nothing works. i tried reformatting my computer installing the latest nvidia driver I restarted and i got blue screen of death... i couldnt fix this i tried running in safe mode but again blue screen of death so i had to reformat again. so now im using my old driver but everytime i go to download the latest driver or a better driver then the one i have it just gives me blue screen of death >_< i used Driver sweeper deleted all display everything to do with nvidia and i still get blue screen of death if i go to update my GFX driver.

my comp specs are listed below

motherboard : p31-ds3l
cpu : E6550 @2.33GHz
GFX : (EN9800GTX+ Darknight)
psu : 550 Thermaltake
case : antec 900
ram : kingston 800 speed DDr2 - 3.5gb
os : xp 32bit

any help on how i fix this problem would be greatly appreciated

thanks

daninozz

i just finaly updated all my computer parts and got my latest driver working without blue screen of death lol all works well issue solved.