I deleted it cause I was running out of space on my SSD, and the preload was open for the full game... but probably something along the lines of max for everything, multi-core rendering enabled, etc.
There have apparently been a number of bugs with the demo, though, so I wouldn't let that bother you.
Also, maybe this is relevant? http://forums.techguy.org/hardware/550880-two-games-running-source-engine.html
At any rate, I just ran this search, maybe you'll find something of value here: http://www.google.ca/search?q=source+engine+online+freeze&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-GB:official&client=firefox-a







