I at one point used a IS7-E as my primary board and have replaced it with an AI7, and have bought a second AI7 that is in my media PC. I find these to be the best boards of the i865pe persuasion. These boards are best suited for Northwood-family processors, as their cpu power supply sections start woking noticeably hard with Prescotts above ~3.2GHz. The AI7 produces winning OCs, razor-sharp memory timings, and superior performance per clock cycle as compared to the alternatives.
The IS7 is almost as capable, and will in fact drive Prescott cpus better due to a bit more beef in the PWM mosfets. But they are really still a half measure for Prescott use. The IS7 vdimm stops at 2.8V, where the AI7 allows 3.2V, but the modification to increase the IS7's to 3 or 3.1V is easy enough. But even though I modded the IS7 to 3V and have had the AI7 for some time, I haven't had a situation where voltage beyond the IS7's 2.8V really made the difference for a particular configuration.
Both boards are laid out pretty well, and the IS7 matches the AI7 feature-wise, with firewire and ICH5R raid. The integrated audio and ethernet are basic but functional on both. I like the AI7 better, but either is a dynamite performance board for a Northwood and you can do ever so much worse.
All this said though, at this point I would purchase an Asus P4P800-SE to allow in later installation of a Pentium-M processor, the only thing I see as a drastic improvement over a P4-2.8c or 3.0c at whatever OC it produces. Even a 3.0C at stock clock is good enough for nearly anyone from a functional standpoint as long as it is married to a strong i865pe board with good dual channel PC3200 memory running good timings.
But once you establish that baseline, the game goes back to how much cpu power you can generate, and while the AI7 is an extremely elegant and potent device the P4P800-SE will give you a cost effective way to increase cpu power to a level for many tasks equivalent to a ~5GHz P4, making it a great value for the ~$250 price a P-M chip and Asus CT-479 adaptor carries. It will extend the useful lifespan of a i865pe rig, making a desire to use PCI express graphics the thing that will force their eventual retirement.
