Why didn't you...?
I wish I could have included results here for a number of interesting CPU models, including the X2 3800+'s most direct competitor, the Pentium D 830. The reason I didn't include them is simple: lousy multiplier control. I couldn't get the motherboards in my test rigs to clock down some of these CPUs to lower speeds in order to simulate lower-speed-grade processors. That's why you won't see results here for the Pentium D 830, and that's mostly why there are only three of the five Athlon X2 models represented. Sorry about that. We will try again next time around with different motherboards.

Our testing methods
As ever, we did our best to deliver clean benchmark numbers. Tests were run at least three times, and the results were averaged.

Our test systems were configured like so:

Processor Pentium D 820 2.8GHz Pentium 4 660 3.6GHz
Pentium D 840 3.2GHz
Pentium Extreme Edition 840 3.2GHz		 Pentium 4 Extreme Edition 3.73GHz Athlon 64 3500+ 2.2GHz (Venice)
Athlon 64 3800+ 2.4GHz (Venice)
Athlon 64 4000+ 2.4GHz (130nm)
Athlon 64 FX-55 2.6GHz (130nm)
Athlon 64 FX-57 2.8GHz
Athlon 64 X2 3800+ 2.0GHz
Athlon 64 X2 4200+ 2.2GHz
Athlon 64 X2 4800+ 2.4GHz
Pentium 4 670 3.8GHz
System bus 800MHz (200MHz quad-pumped) 800MHz (200MHz quad-pumped) 1066MHz (266MHz quad-pumped) 1GHz HyperTransport
Motherboard Intel D945GTP Intel D955XBK Intel D955XBK Asus A8N-SLI Deluxe
BIOS revision NT94510J.86A.0897 BK95510J.86A.1152 BK95510J.86A.1234 MCT2/dualcore
BK95510J.86A.1452
North bridge 945G MCH 955X MCH 955X MCH nForce4 SLI
South bridge ICH7R ICH7R ICH7R
Chipset drivers INF Update 7.0.0.1019 INF Update 7.0.0.1019 INF Update 7.0.0.1019 SMBus driver 4.45
IDE driver 4.75
Memory size 1GB (2 DIMMs) 1GB (2 DIMMs) 1GB (2 DIMMs) 1GB (2 DIMMs)
Memory type Corsiar XMS2 5400UL DDR2 SDRAM at 533MHz Corsiar XMS2 5400UL DDR2 SDRAM at 533MHz Corsiar XMS2 5400UL DDR2 SDRAM at 667MHz Corsair XMS Pro 3200XL DDR SDRAM at 400MHz
CAS latency (CL) 3 3 4 2
RAS to CAS delay (tRCD) 2 2 2 2
RAS precharge (tRP) 2 2 2 2
Cycle time (tRAS) 8 8 8 5
Hard drive Maxtor DiamondMax 10 250GB SATA 150
Audio Integrated ICH7R/STAC9221D5
with SigmaTel 5.10.4456.0 drivers		 Integrated ICH7R/STAC9221D5
with SigmaTel 5.10.4456.0 drivers		 Integrated ICH7R/STAC9221D5
with SigmaTel 5.10.4456.0 drivers		 Integrated nForce4/ALC850
with Realtek 5.10.0.5820 drivers
Graphics GeForce 6800 Ultra 256MB PCI-E with ForceWare 71.84 drivers
OS Windows XP Professional x64 Edition
OS updates -

All tests on the Pentium systems were run with Hyper-Threading enabled, except where otherwise noted.

We have included results for the Pentium D 840 in the following pages. We obtained these results by disabling Hyper-Threading on our Extreme Edition 840. Since the Pentium D 840 is just an Extreme Edition 840 sans HT, the numbers should be valid. Similarly, the Athlon 64 3500+ scores you'll see in the following pages were obtained by underclocking an Athlon 64 3800+ (with the new "Venice" core) to 2.2GHz. The performance should be identical to a "real" 3500+.

Thanks to Corsair for providing us with memory for our testing. Their products and support are both far and away superior to generic, no-name memory.

Also, all of our test systems were powered by OCZ PowerStream power supply units. The PowerStream was one of our Editor's Choice winners in our latest PSU round-up.

The test systems' Windows desktops were set at 1152x864 in 32-bit color at an 85Hz screen refresh rate. Vertical refresh sync (vsync) was disabled for all tests.

We used the following versions of our test applications:

The tests and methods we employ are generally publicly available and reproducible. If you have questions about our methods, hit our forums to talk with us about them.