Systeme crash continously

hi im new here and want some help
i got a 1 year old coputer
pentium 4 -1.9GHz
512 meg ram
80 gb hard drive
nvidia gforce mx400 with tv out

ok here my trouble
i have updated all my driver and they all sign microsoft<—B.S

anyway
im building game for my own pleasure with NWN aurora tool set
and im hosting this game on a dedicated server from my pc
every time i try to do somthing like scripting .building(compiling),or what ever i crash and systeme reboot and somtime a blue screen appear telling my IRQL_NOT_LESS_OR_EQUAL

but now is become more anoying is i look a video or i type a text with microsoft word i crash also

effectivly i will have a gaz and i maybe crash

i have check up every thing dxdiag nothing
chkdsk nothing
updated to lastest driver from my manufacturer for my video card crash also
also if i restart my computer dont respond and stand black and dont reeopen

or if i run my server and go sleep in the morning i will have to CTR+ALT+DELT to be able to activate the mouse and the computer coz is like freeze

i have open my computer to see if somthing wrong but didnt find nothing exept a little spot on my mother board is it possible my mother board is fry?
and if is it how come i can still use my computer and my systeme dont warn me
but the spot is really minime and the color is not dark but justr a little brown

anyway

i do this before to send my computer to repair shop and cost me $$$

HELP!!!

HOW TO: Debug a System After You Receive Stop Error IRQL_NOT_LESS_OR_EQUAL (0xA)

You never said what OS you’re running, or version of windows.

That error you get is 'caused by IRQ conflict. Common in older mobos that don’t have enough IRQ address to spread around. Switch your PCI components around a bit and if you could, manually assign IRQ to devices in BIOS. In windows, go to System Info > Hardware Resources > IRQs and check which devices are sharing IRQ. Also, which sound card are you using? One last thing, you don’t have to install every freaking update MS puts out, only the major patches.