Wondering which processor is best for Half-Life 2? Or perhaps you're curious to see how older Athlon XP processors perform with this game in comparison to Pentium 4 and Athlon 64 processors? In this article we've rounded up 17 different processors ranging from the Athlon XP 2100+ all the way up to the Athlon 64 FX-55 and Pentium 4 3.46GHz Extreme Edition. See how the CPUs compare to one another inside!