Use a memory usage parser to check for applications using memory, I notice the usual CS:S hl2.exe application running, but looking at specific memory instructions it seems as though when loading a map an memory instruction hooks to game's process and then looks at the instructions, at least thats what I think its doing. All I can see is the game having a seperate instruction set running during connecting to a server.

Is this VAC?

DougV: VAC will be here in the not too distant future and will catch a lot of people by surprise.

VAC doesn't scan all the .exe files on your comp, just the ones that are running in memory.

DougV: VAC will be here in the not too distant future and will catch a lot of people by surprise.

If I were you, then I wouldn't attach too much value to Doug's statement. VAC may recieve an update in the "not too distant future", but it will be an one-time event. After the comming update, VAC will go into unattended mode again which will remain unattended for another six months . . .