All steam games lock-up after few minutes

[Weren]

Anyone else experiencing this problem?

http://forums.steampowered.com/forums/showthread.php?t=843016

I've had this problem for a month now.
I have tried almost everything, but so far nothing have helped. Problem is still waiting for solution. 
And it seems that many other peple are suffering from this too.

So i came here to ask, if any of you have seen this thing and/or if you would know the salvation for it?

EDIT: And yea, it's just the online steam games, i can play hl2 or other nonsteam online games just fine.

 

[Suspect-Device]

I had this problem a while ago, it turned out it was overheating, although that has already been detailed in the link you provided.

Usually you have to crack your case open and just make sure there's no dust clogging up fans and components.

 

[Weren]

Didnt work, i already did that a week ago with no results.

 

[Archonsod]

Turn off everything else using your internets while running Steam.

 

[Weren]

I did that. Anything that could be using my internet are Java and a process called iuser.exe, so i turned them off, but that didnt help.

Also my Antivirus program is using it. Should i disable it too?

EDIT: When playing L4D i found process named: "steam game overlay", from taskmanager. I turned it off, and i was still able to play, but then it locked-up again.
So Turning it off didnt neither help or make it worse.

 

[Sir Prince]

Steam game overlay is the Steam Community feature which while playing let's you bring up your friendslist, profile, even a web browser when you press shift+tab.

 

[Weren]

Oh it was that.