Well, most games such as AH will use your CPU as much as it can to get the maximum framerate. I think you will find any game will suck up 100% of your CPU.
More to the point, tell us a bit more about your DSL setup, since it seems to be causing the problem. How does the DSL device connect to your computer? USB perhaps?
------------------
Lephturn - Chief Trainer
A member of The Flying Pigs
http://www.flyingpigs.com "A pig is a jolly companion, Boar, sow, barrow, or gilt --
A pig is a pal, who'll boost your morale, Though mountains may topple and tilt.
When they've blackballed, bamboozled, and burned you, When they've turned on you, Tory and Whig,
Though you may be thrown over by Tabby and Rover, You'll never go wrong with a pig, a pig,
You'll never go wrong with a pig!" -- Thomas Pynchon, "Gravity's Rainbow"