Benchmarks with Doom 3 - 64-bit mode OpenGL Gaming Performance

32-bit gaming under Windows XP Pro x86 Edition is a very different ball of wax for these new Pentium 4 processors. In our Doom 3 tests in 64-bit mode, the Pentium 4 drops back 20% from its 32-bit scores whereas the Athlon 64 only gives up about 10%. Once again, however, it's almost speculative to judge all that much because the OS is beta and this is the P4's first release with EM64T support. 

Benchmarks with Half-Life 2 - 64-bit mode DirectX 9 Gaming Performance

More of the same here, with the same relative scale in performance degradation between the Pentium 4 and Athlon 64. If you're a gamer, there's no use delving into the world of beta 64-bit OSes at this point in time. Let's move along.