DiVX Encoding	Source: PCStats

The DivX encoder benchmark contains both a 32-bit and a 64-bit benchmark that measures the performance of raw video encoding of the AMD optimized DivX video encoder version 503. The encoder has been optimized for AMD Athlon 64 and AMD Athlon 64 FX systems (both 32-bit and 64-bit). Higher FPS is better.

Divx Encoder:
32bit:	FPS	Ranking
WindowsXP 32-bit Stock (2.4 GHz)	157.82
WindowsXP 32-bit Overclocked (2.64 GHz)	179.17
WindowsXP 64-bit Stock (2.4 GHz)	166.42
WindowsXP 64-bit Overclocked (2.64 GHz)	182.24
64bit:	FPS	Ranking
WindowsXP 32-bit Stock (2.4 GHz)	0
WindowsXP 32-bit Overclocked (2.64 GHz)	0
WindowsXP 64-bit Stock (2.4 GHz)	208.59
WindowsXP 64-bit Overclocked (2.64 GHz)	226.04

When the system is overclocked, both platforms experience similar performance boost due to overclocking, while the WindowsXP x64 Edition enjoys an overall performance advantage. 64-bit only mode is noticeably but not massively faster.

CINEBENCH 2003	Source: Cinebench

CINEBENCH 2003 is the free benchmarking tool for Windows and Mac OS based on the powerful 3D software CINEMA 4D RX. The tool is set to deliver accurate benchmarks by testing not only a computer's raw processing speed but also all other areas that affect system performance such as OpenGL, multithreading, and multiprocessors

Cinebench 2003
Rendering 1CPU:	Points	Ranking
WindowsXP 32-bit Stock (2.4 GHz)	338
WindowsXP 32-bit Overclocked (2.64 GHz)	372
WindowsXP 64-bit Stock (2.4 GHz)	341
WindowsXP 64-bit Overclocked (2.64 GHz)	374
C4D Shading:	Points	Ranking
WindowsXP 32-bit Stock (2.4 GHz)	404
WindowsXP 32-bit Overclocked (2.64 GHz)	445
WindowsXP 64-bit Stock (2.4 GHz)	410
WindowsXP 64-bit Overclocked (2.64 GHz)	448
OpenGL SW-L:	Points	Ranking
WindowsXP 32-bit Stock (2.4 GHz)	1922
WindowsXP 32-bit Overclocked (2.64 GHz)	2113
WindowsXP 64-bit Stock (2.4 GHz)	1943
WindowsXP 64-bit Overclocked (2.64 GHz)	2125
OpenGL HW-L:	Points	Ranking
WindowsXP 32-bit Stock (2.4 GHz)	4173
WindowsXP 32-bit Overclocked (2.64 GHz)	4597
WindowsXP 64-bit Stock (2.4 GHz)	4218
WindowsXP 64-bit Overclocked (2.64 GHz)	4602
OpenGL Speedup:	Points	Ranking
WindowsXP 32-bit Stock (2.4 GHz)	10.33
WindowsXP 32-bit Overclocked (2.64 GHz)	10.34
WindowsXP 64-bit Stock (2.4 GHz)	10.29
WindowsXP 64-bit Overclocked (2.64 GHz)	10.27

Overclocking results are similar on both operating systems, which should be great news for enthusiasts who want to stay with cutting-edge software.