Phoronix compared the performance of Doom 3 v. Quake 4

Now that Quake 4 has been available here in the United States for a couple of days along with the Linux client and server binaries, we've gathered some results comparing the frame-rate performance of Quake 4 against Doom 3, as Quake 4 is using a tweaked version of the Doom 3 engine.

Doom 3 v. Quake 4 Performance