These chipset are for dual opteron motherboards:
nVidia nForce Pro 2200 & 2050 or AMD® 8131 HyperTransport PCI-X Tunnel
AMD® 8111 I/O Hub

We're talking about performance from processors, memory, hardrives, and motherboard bandwitch assuming they have the same setup(same ram cpu....)

We are also talking about features that touch processors, hardrive, ram, hardrive controllers that are different in each motherboard.

We're not talking about how for example, one has pci express and the other only agp, thats not the issue(video,audio and any relates are not the issue)

Everything related to the actual speed of the computer using these chipsets is the issue.

Was looking throught tom hardware site, didnt find what I was looking for.
If you know a good link that compares both, paste it.
If youve personnally tried both, feel free to speak your mind about your experience.

As my experience with the low end msi dual motherboard with dual opteron 1.8ghz and dual ddr 400 ecc, was trajecal(speed was like a low end celeron)
For one I bought the wrong ram(need 333 ecc) and two the motherboard only has one memory channel for both processors)

It would be useful to restate your question. Please repeat the motherboard models by brand, as something seems missing. Otherwise, it seem you want so much information that it will be difficult to offer a useful reply. Nearly all of what you ask is available at the website of the board manufacturers.