I have a P2-350 system with built in AGP (ATi) - the upgrade path for this box involves a brain transplant courtesy of Powerleap and a vid card addition - unfortunately it has to be PCI.
What I find interesting about the whole NVS thing (Zenith's posts) is that is says that nVidia hasn't worked all the kinks out of multiple GPU's in the AGP slot. It seems to me that 3dfx had that part down pat, and seeing as nVidia has many former 3dfx employees as well as its technology that it should be a no brainer to implement the technology in this brand new part.
You might be able to find a Geforce 3 (note i said might). I have seen a few 2's in pci. But there will probably not be any 4's in PCI. The bus is just to limiting for the card and the market is not that big since 95% of people have AGP slots. Heck they have been standard on boards for a long time now. Tell me what socket cpu you have and Im sure we can find you a cheap mobo with an agp slot (the older your chip the cheapr the mobo <g> ).
Note that the GeForce4MX 420 has only a 128-bit SDR memory bus (similar to the original GeForce2 MX and MX400). This will underperform the 128-bit DDR memory on the GeForce4MX 440 and GeForce4MX 460.
I haven't seen a head-to-head benchmarks, but for PCI you might still be best off with the Radeon 7000 DDR.
With either the Radeon 7000, GeForce4MX or GeForce2 MX, you are looking at DirectX 7 hardware T&L. You will not get the programmable shaders in the DirectX 8 boards like the GeForce 3, Radeon 8500, or GeForce4Ti.
Sorry, not interested in anything other than nVidia. Call me a bigot but I'll stick with what works - especially in terms of ATi's driver issues (which still bite me from time to time).
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