What about the P4X400?
Since we've included results for the VIA P4X333 chipset below but not the new P4X400, I should explain a few things. First, the P4X333 is one of the oddest (and least vaporous) cases of vaporware I've seen. VIA sent us a P4X333 reference board for testing with a PR rep attached, and we proceeded to review the chipset in anticipation of P4X333-based products hitting the market soon. Yes, there's an ongoing legal fight between VIA and Intel, but VIA itself and key partners like Shuttle were selling VIA-based Pentium 4 boards regardless. The chipset performed well, and our review was fairly positive as a result.

Weeks passed. Readers wrote us asking where they could buy P4X333 boards, and no one had an answer. The P4X333 was AWOL.

Now, the P4X400 has apparently launched—this time for real. Shuttle and Soltek boards are rumored to be hitting the channel, and some publications received VIA-branded P4X400 boards (not reference boards, but full-blown products) to review. Unfortunately, we weren't one of those publications, so we aren't able to include the P4X400 here today. P4X333 test results appear below as an interesting little curiosity. We should have a P4X400 board soon, and we'll review it then.

The method to our madness
We tested with a lot of different configurations for this review, so hold on. You're about to see a lot of info here, and the table below will be important to understanding the results. For instance, we tested the Intel 845G chipset in three configurations: with DDR266 memory, with DDR266 memory using the 845G's built-in graphics, and with DDR333 memory. (Although the 845G doesn't officially support DDR333, the chipset is entirely capable of running the memory at DDR333 speeds, unlike the 845E.)

That said, I wish we'd had time to include a few other configurations. For instance, take the Intel 845E. Simple time constraints prevented us from testing with the 845E and including results. For what it's worth, the 845G results should be very, very similar to what you'd get out of an 845E.

Also, please keep in mind that chipsets, when they're put together well, shouldn't affect overall system performance too drastically, all other things being equal. The key to better performance in current chipsets is usually the memory controller; chipset makers tend to optimize their memory controllers over time to squeeze out more performance. Support for faster memory types like DDR400 and PC1066 RDRAM will really make a difference, too. The performance results you're about to see may not show the kind of eye-opening mega-differences you'd expect out of a new CPU or graphics chip. That's expected with chipsets.

As ever, we did our best to deliver clean benchmark numbers. Tests were run at least twice, and the results were averaged.

Our test systems were configured like so:

Athlon XP Intel 845 Intel 845G Intel 850 Intel 850E SiS 648 VIA P4X333
Processor AMD Athlon XP 2200+ 1.73GHz Intel Pentium 4 2.4GHz Intel Pentium 4 2.4GHz Intel Pentium 4 2.4GHz Intel Pentium 4 2.4GHz Intel Pentium 4 2.4GHz Intel Pentium 4 2.4GHz
Front-side bus 266MHz (133MHz double-pumped) 400MHz (100MHz quad-pumped) 533MHz (133MHz quad-pumped) 400MHz (100MHz quad-pumped) 533MHz (133MHz quad-pumped) 533MHz (133MHz quad-pumped) 533MHz (133MHz quad-pumped)
Motherboard Shuttle AK35GT2/R Abit BD7-RAID Abit BG7 Intel D850MD Asus P4T533-C SiS 648 reference P4X333 reference
Chipset VIA KT333 Intel 845 Intel 845G Intel 850 Intel 850E SiS 648 VIA P4X333
North bridge VT8367 82845 MCH 82845G MCH 82850 MCH 82850E MCH SiS 648 VT8754
South bridge VT8233A 82801BA ICH2 82801DB ICH4 82801BA ICH2 82801BA ICH2 SiS 963 VT8235
Chipset drivers VIA 4-in-1
4.38(2)v(a)		 Intel Application Accelerator 6.22 Intel Application Accelerator 6.22 Intel Application Accelerator 6.22 Intel Application Accelerator 6.22 AGP 1.10.03
IDE 1.01.13		 INF update 1.50 beta
AGP 4.11 beta
IDE filter driver 1.20a
Memory size 512MB (2 DIMMs) 512MB (2 DIMMs) 512MB (2 DIMMs) 512MB (4 RIMMs) 512MB (4 RIMMs) 512MB (1 DIMM) 512MB (2 DIMMs)
Memory type Corsair XMS3000 PC2700 DDR SDRAM Corsair XMS2400 PC2100 DDR SDRAM Corsair XMS2400 PC2100 DDR SDRAM

Corsair XMS3000 PC2700 DDR SDRAM		 Samsung PC800 RDRAM Samsung PC800 RDRAM

Samsung PC800 RDRAM at 1066MHz		 Corsair XMS3000 PC2700 DDR SDRAM

Corsair XMS3200 DDR400 SDRAM		 Corsair XMS3000 PC2700 DDR SDRAM
Graphics NVIDIA GeForce4 Ti 4600 128MB (Detonator XP 28.32 video drivers)
Sound Creative SoundBlaster Live!
Storage Maxtor DiamondMax Plus D740X 7200RPM ATA/100 hard drive
OS Microsoft Windows XP Professional
OS updates None

Thanks to Corsair for providing us with memory for our testing. This memory is undoubtedly some of the best stuff on the market. Their XMS3000 DIMMs were actually able to overclock and run stable at DDR400 with conservative memory timings, and the new XMS3200 memory was able to run at 400MHz using moderate timings (though still at CAS latency 2.5, of course).

I should note that we're using the Intel Application Accelerator drivers instead of the older Ultra ATA drivers. We elected to go this route because Intel is replacing its Ultra ATA drivers with IAA. In addition to providing support for Ultra ATA modes, the Application Accelerator does some prefetching to improve I/O throughput, so products based on Intel chipsets may have a slight advantage as a result. But then, that's the point. We're hopeful other chipset manufacturers will incorporate similar performance-boosting measures in their drivers, as well—if they haven't already.

The test systems' Windows desktops were set at 1024x768 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:

All the tests and methods we employed are publicly available and reproducible. If you have questions about our methods, hit our forums to talk with us about them.