Microsoft Windows XP Media Center Edition 2005: Feature and Performance Investigation

The Final Test

The only way Microsoft can justify the price of a Media Center PC is by offering it as a multipurpose machine, as a Media Center PC as well as your regular family, office, gaming or whatever-else-you-do-with-it PC. The problem with this scenario is, as we just established, that Media Center takes up quite a bit of horsepower when you're using it as intended. So how usable are these machines as multitaskers between recording TV shows and doing everything else you do with your PC?

Anytime you switch between the Media Center interface and the XP interface, the entire system pauses - video, audio, everything. The pause is annoying and will sometimes interrupt whatever it is you may be recording; this pause is present regardless of how fast or how slow your CPU is; it will occur when going from a full screen Media Center interface to a windowed one, or when simply minimizing the Media Center interface.

Luckily for Microsoft, most users don't run through the program guide while typing in Word or watch TV while they're gaming. Most of the time the Media Center interface will actually be closed while the user is doing something else with their PC. Microsoft understood this and thus allowed Media Center to continue to record scheduled shows even while the interface was inactive. Which leads us to our next question, how much overhead is there when the Media Center interface isn't running, but the system is still recording a show?

When you're just watching TV on a MCE box, quite a bit is happening on the inside, keeping your entire system busier than most people probably ever tax their machines. The video present on your screen is being encoded and decoded in real time in front of you, which is the cause for most of the high CPU utilization that you get when just "watching TV." But if you aren't watching the TV, just recording what's on a particular channel, then you're only encoding the data that comes into the TV tuner, there's no decoding done - so less of your CPU is used. How much less? Quite a bit.

While our fastest platform had about 21% of its CPU power in use while watching TV, only 6.5% of its time was used when simply recording a show in the background. While that's more CPU power than playing an MP3, it still leaves quite a bit for you to complete other tasks. Even the mid-range configurations only had about 10% of their CPU power tied up, leaving the system very free to do many other things.

There is one limitation to keep in mind here however. While we see that recording a single show without displaying it on the screen at the same time does not require much CPU power, thanks to the hardware-assisted encoding of ATI's eHome Wonder card, don't forget that all of this recording is giving your hard drive a good workout. We tried launching MS Paint while recording just a single show, and a normal instantaneous program startup was instead replaced with a 5 second program startup, all thanks to the single hard drive in our test bed. The way around this problem is to have a second drive, and to have Media Center record all of its programming to a hard drive separate from the one the rest of your applications are on.; this is a necessity if you plan on using your MCE machine as a regular PC while it goes about its Media Center duties. Through the recorder settings you can tell Media Center to store its buffer and recorded shows on a separate hard drive; problem solved.

Next we wanted to see how much of an increase in CPU utilization there was by recording two shows simultaneously, once again, outside of the Media Center interface.

Here we see that the performance hit isn't too bad until we get much slower than 1.6GHz, but even then it's not horrible.

With over 80% of your CPU going unused, that's plenty of horsepower to work on documents, surf the web and even play a few games. With the right processor, MCE 2005 can definitely be used as the all purpose PC that Microsoft wants it to be. The thing to keep in mind is that the stability of the system will definitely be pushed to the limits; running MCE has shown us that poorly written drivers, overly aggressive memory timings and general hardware instability definitely won't cut it under this type of load.