Lame and OGG performance is almost completely based on CPU power, and thus awards Dell's higher clock speed proportionately.
3D Studio Max gets a little bit less boost from Dell's higher CPU clock speed.
3D Mark 2005 shows the high-priced Dell with much larger performance gains than those seen in the Doom 3 and F.E.A.R. game benchmarks, but the difference is still close to that observed in Oblivion.
SPECviewperf's Maya and Ensight viewsets show gains far exceeding the clockspeed and graphics configuration advantages of the Dell 720 H2C. Also strange is the fact that the slower Gateway FX530XT managed to win a few viewsets.