Unbelievable crash with B1900 series

hi guys can anyone suggest something for my problem?
I -ve recently bought a Presario B1900 series in Taiwan , and this is what i did right after buying: format the HD , and install win vista ultimate, as for default the laptop was mounting only win vista basic, then didnt even touch its drivers , just use those that vista was providing by default, and after few days i went back to the shop to buy an addictional 1gb of ram.
So i gave them back the 2 banks of 512 , add some cash and bring back 2 banks of 1gb each. Then after few days a problem came up : after some time during the routine use of my os , suddenly some colored lines will pop up over all my screen and turn all of it in a sort of full screen colored bar-code, freezing all my activities and no matter what i press , ctr alt canc , or esc , it's like the machine is hanged , so i have to press the power button to turn it off and reset and i get back to use it until the same problem occur again...
it can happen after 10 min or 2 hrs , and whatever software i am using...
so i started to try everything i could to find out where the problem was coming from . reinstalling vista , try to update all the drivers , installing the drivers from the compaq website , rolling back the drivers , enabling / disabling processes , scanning for viruses , reinstalling reformatting repartitioning everything , but the problem occurred even just after a new installation with the os completely clean !!! , so now i started to think that those banks of ram were not 100% comatible with my laptop, do you guys know if that could be the possible explanation for my crash?
thanks a lot if you could please help a bit , im driving myself nuts

here i attach a picture that i took to give a better idea , yea i know it looks like a virus but it's not!

 

can anyone say "busted video card" ?

 

I think its the RAM

 

Check for both.
Scan for artifacts with Atitool and scn for memory errors with memtest86+

 

im doing in this moment a test with memtest86+ as suggested by u guys , it's running since almost 3 hours , i left the default options by the way, but i dont understand if i have to stop it manually or it will end by itself, anyway i read PASS=2 , errors=0

 

in the meanwhile i phoned the hp support and they told me that it could be a VISTA related problem as i have 2gb installed , vista is giving troubles while assigning too much memory for the video card which is integrated and they said to try to assign less memory to it , or either test the pc with only 1 gb of mem! .... well guys what do you think ???
by the way my memory test is still on , passed 4 times , ove 6 hours 0 errors.... sob!!! cant understand

 

Naw I think its the video card

 

how can i check if it's the videocard , .... with that atitool , i cant really understand what to do to see directly if the video card is OK or not , what kind of test should I run? or are other utils to make similar tests?

 

atitool has a window that tests the video card, with that window ppl test whether their overclock is ok or not. if the graphics in the window have artifacts, then there is something wrong.

and thats not a virus, it cudnt really be one if u reinstall/format and its still there.

think its ur video card as others have stated

 

i am testing the video card with atitool, this is what happened : cliccking on find max core , after 3 seconds the screen will turn green and freeze everything ..need to reboot ... by clicking on find max memory the same thing is happening ...
what does that means ? is my video card f***ed ?

 

hello??? anybody out there??

 

so you ran the test and it froze up and turned green.. yep its the vid card.. time to call HP for a warranty repair.

 

yes it turned green only when I press FIND MAX CORE or FIND MAX MEM

 

Have experienced that before, although not with my b1909 but with my older presario b1800. Cause of it was the incompatibility with the RAM.

 

I have now bought a KINGSTON 1gb block of ram and i am just running the system with it, and it seems to be runnning fine... no more crashes .
I also tried to add another 1gb (brand trascend) but with 2gb i still experience crashes ...
what could it be

 

I updated the bios to F.15 , but sometimes it seems not to boot properly and it crashes at the compaq logo.
The times that it starts will work perfectly.
I might decide to buy an original bank of memory from HP ... what do you think ? like gregg said it might be incompatibility of ram

 

I found out that they cannot take my laptop under warranty because the ram slots were opened and i changed the original ram with another.
So the problem now seems that the laptop still crashes from time to time and most of the time it seems when i run a DVD video with windows media player, not with another software like vlc ... but it seems a video card related issue... (right now im still mounting 1 bank of kingston 1gb and another or Trascend 1gb by the way) maybe with 2 gb the amount of video ram assigned automatically make the system crash with certain applications????
any HELP please????????????

 

Hey Nosham, that's bull, except for the new RAM that you bought, everything is still original, so you can insist for its warranty... Btw, bought an extended battery, at least I can reach about 2:45 min. already..