Motherboard needed?

I have a Dell Studio XPS 16 (1645) that has crashed on me.  When I say "crashed", the screen goes fuzzy, gets lines, etc. after it gets warm, and then eventually I get the dreaded blue screen, the computer restarts, etc..  Because the screen is so messed up, I am unable to read the associated blue screen error.  After the machine had been shut down for a while (cooled off), I was able to start it up and run the Dell diagnostic which confirmed the video card had failed and caused the blue screen.

I've been in contact with Dell parts who told me I can't just replace or get a video card - I have to get a replacement motherboard (Part #WDH9C).  I spoke to them again today, and they don't have any available - neither new nor refurbished.

Would anyone have more advice on this matter or know of anywhere else I might be able to get a new board?

Should someone at Dell reply, the Service Tag # is

Thank you.