As you can see, the Pavilion a400z clung to the bottom of all four speed tests. It only edged out the single core eMachines T3642 on tests where having multiple cores has an impact, such as Photoshop. You'll notice that the eMachines T5246 beats the HP on every test, though, and by a significant margin. The reason is because that eMachines model has a 1.8GHz AMD Athlon 64 X2 4000+ chip in it. Now imagine if the HP were configured to match but included the even faster 2.3GHz Athlon 64 X2 4400+. Without actually testing it, we can only speculate how an upgraded version of the a6400z might perform, but all indications are that it would deliver the best bang for the buck in this price category.