HL2 video crashes/minimizes to desktop, can still hear/control game with mouse

[FrankAZHP]

I'll be in the middle of playing when the game will do the audio loop while level/items etc load but instead of being fine after a moment it crashes my video only (or minimizes it) to where I see my desktop.
I can then still control the game via mouse and keyboard (move/shoot/jump/etc) without seeing the game.
If I try to alt+tab and then click on the minimized HL2 box it will not bring up the game video (although then it will resume my mouse/keyboard movement)
If I try to go to processes and "Bring to front" it does not work either. I'm forced to kill the process and then restart the game.

Win7 64bit
9800 GTX+

Graphics drivers are up to date
Already tried compatibility mode for XPSP3
Could be a Windows Update messing with DX like what happened with Bioshock 2 a few months ago.

Anyone experience the same issue that can provide insight?
Thanks in advance.

EDIT1- Still no fix. Been playing all the way thru Ep1 and thru Ep2 with the same issues and I have to save a lot.
When the save is loaded it seems to load the map area ahead of me so I can get ahead for a while before it happens again. Still frustrating. Will update this will info when/if I come across it.

[FrankAZHP]

bump