Any Idea What Would Cause This?

[hexagram23]

Recently I got "The Orange Box" and right now I'm playing "Episode 2".

To make a long story short the game has been glitching, like this:
http://i51.photobucket.com/albums/f4.../HL2Glitch.png
http://i51.photobucket.com/albums/f4...HL2Glitch2.png

That's a comparison pic. And it doesn't always do it, I could turn the game on right now and see that, but next time be in the same area and it'll be perfect. For some reason when ever there is tunnels, openings, etc. you can see right through them into the back ground. The actual textures, etc. don't appear until you "zone" past the entrance.

I've played through "Portal", "HL2" and "Ep 1" and didn't see anything like this, so I dunno. I've also tried uninstalling/reinstalling it which had no effect.

I use Vista and have an Nvidia 8800 GTS, also 3 Gigs of RAM. Not sure if any of that info is useful in this scenario though. Also here is what I have the game set to, although changing the config doesn't seem to help/hurt this problem either way:
http://i51.photobucket.com/albums/f4...HL2Glitch3.png

Thanks for any info you can give me.

[hexagram23]

Ok now I'm really confused.

I just loaded "Portal" and now it has weird glitches too. This game and "HL2: Ep2" were fine a couple days ago. Also I played "FFXI", "HL2". "HL2: Ep1", "Bioshock", and "Mass Effect", none of those games have any problems.

Anyway here is pics of the glitches from "Portal"....first the glitch, then a normal pic....the glitch goes away if I shoot the Portal gun at it:
http://i51.photobucket.com/albums/f4...talGlitch2.png
http://i51.photobucket.com/albums/f4...tch2Normal.png

http://i51.photobucket.com/albums/f4...talGlitch1.png
http://i51.photobucket.com/albums/f4...itchNormal.png

I'm trying to get help from the Valve boards but the Mods are taking forever to verify my account....a guy over there has sort of the same problems.

Thanks.

[Norellicus]

The HL2 effect is much like one I see in WoW when I turn up the draw distance too far, so try turning that down first.

I have no clue what could be causing that issue you're seeing in Portal though. It doesn't look like GPU artifacting or anything I've typically seen. Try deleting your local Portal cache from steam and redownloading the local files, maybe got a corrupt texture loader or something.

[hexagram23]

The HL2 effect is much like one I see in WoW when I turn up the draw distance too far, so try turning that down first.

I have no clue what could be causing that issue you're seeing in Portal though. It doesn't look like GPU artifacting or anything I've typically seen. Try deleting your local Portal cache from steam and redownloading the local files, maybe got a corrupt texture loader or something.

Today several people have reported similar problems over on the Steam Boards. I guess Valve patched something recently and it broke "Ep2" and "Portal", so it's not a problem on my end. They just need to roll back the patch and/or fix it.

Thanks anyway for the response.