Distorted display on everything

Hi guys, I have just experienced a very rare and also very annoying problem with my Dell.  The display is jumbled and glitchy. the DELL opening screen is like a messed up puzzle, it flashes and colors are distorted too.  I'll post pictures when i can.

These are the specs:

dim 8200, 512MB RDRAM, 2.0 GHz P4, 40 GB HD, xp home, ati 9800 pro 128mb video, etc.

I'll tell it like it happened.  I used one of those aerosol dusters from Fry's and i was cleaning the inside.  I blew the mobo and the video and anywhere else with dust.  I bring it back inside and power up.  This is when it starts.  The display is distorted, the boot screen is laggy/shaky and its painful to look at. I've no idea HOW this happened and WHY its happening. ive concluded its not the monitors fault as I've tested both DVI and VGA outputs as well as testing it on a TV with S-video out - all the same results.  ALSO, this was during a reformat.  I just began to boot from CD after dusting it and performed a clean install of XP.  colors and everything were ugly.  After it finished i tried to install drivers immediately, now the display wont even show. its worse than before and after 30 seconds, the monitor just plain shuts off.

Im panicking and i dont noe wut to do.  Please help, i'm almost positive its hardware and not software issues.  The duster is Carbon dioxide that blows bursts of air.  If shaken, the duster spits out frost which is white, icy cold, but dissolves.  i dont believe it did that since i was careful to not shake the can, but could that be a reason for the defect?

Much thanks to everyone reading this long post.