Problem with motherboard?

[mSg-1]

Hi

ive got an odd problem with my computer
bought it about a few years ago, and was working fine, but now i guess it isnt.

tech info:: motherboard: ECS K7S5A
geforce 4 mx 440
athlon 1900xp+
windows xp

im not sure where the problem is, but lets just start that ive tried adding another 256ddr memory ram stick to the back for better performance, (both 266mhz) and everything looks ok, its much faster (boot etc..) but when i launch applications like games, it 80% of the times crashes. (blue screen) dump memory error in nopaged area or something.. okay now when I take the other one off, all works fike.
That happened a few days ago. this is what happens now that worries me::
all is okay until i get to the wellcome screen, if i dont type my password within 5sec, the comp just jamms after writing my password, if i write it fast it works okay but same blue screens shows up once every 3 boot. if it doesnt, all works as it should, (exept when playing some videos, they launch the blue screen right up)

could my mother board be broken?
virus ?
options in bios are wrong?

all help is appreciated thanks

[curtybob]

You may try reseating some of the stuff that may have been bumped while you were in there. Try things like the memory, the video card, all the PCI cards, the IDE cables... things like that. You might also try moving the memory you have to different slots and trying them one at a time in all the slots.