In expectance of Half-Life 2 (I'm looking forward to some nice level design with a little bit more variety than Doom 3, also some actual light, not pitch black all the time) I searched the Web for information on it.
I came across the information that Half-Life 1 was based on a tweaked Quake 1 engine. I always thought they had licensed the Quake 2 engine. That explains why the graphics wouldn't really overwhelm me that time, though the gameplay and level design was quite nice. This confounded me utterly, so I took the Half-Life 1 CD I had found some weeks ago while scavenging the cellar for some ancient audio CDs to rip and slapped it into the drive, ready to check it out. The setup.exe didn't want to install. On a XP. It wasn't the actual game that caused trouble, but the setup.exe. It just runs and then exits, no error message.
Anyway, some hourse later I stumbled across Steam. That's the online gaming service of Valve, the creator of Half-Life. The FAQ was terribly inaccurate, but I figured I could play my old Half-Life by downloading it from there, since I had the CD key. I installed it, and the first thing I realized that it behaves sluggish. It seems that everytime I want to move the window on my desktop it has to request permission from the master server to do so. Even when the games list has been downloaded and is displayed and I'm ready for scrolling down to see what else they have, it sometimes has to take a break.
Ok, maybe I'm scrolling to fast. I found a Couterstrike version playable with my CD key. Download started (it's quite big of course, going into several hundreds of megabytes). After some minutes I noticed that my CPU fan was at full throttle, which usually is the effect of some app going wild in using CPU time. It happens during most games, but seldomly when I just surf and download stuff (I have to click very fast to get the fan working hard). But it ran on highest level. So I checked for the app causing this.