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You maybe need a bit more to go on than just wanting an ISA slot.

440 BX
Most Intel 440BX-based motherboards have ISA slot. Mine is DTK prm-00801 E0 which comes with 3 ISA slots instead of 2.

Epox 8KTA3+
This mobo supports Athlon XP Palomino CPU, and has one ISA slot. It also has AGP 2x (3.3 volt) slot, so you can put Voodoo5 5500 video card on it.

Soyo SY-845PE ISA
This mobo supports Pentium 4 Northwood up to 3.06 GHz, and has three ISA slots. However, its AGP slot is 4x (1.5 volt), so if you want to use Voodoo5, you should use Voodoo5 5500 PCI.

I'm using a 8KTA3. and I actually have a Athlon XP with a barton core in mine... It turns out you can stick pretty much any socket A chip in there as long as you take into account the FSB and multiplier settings. Alas it is showing its age.. it has a few capacitors that are bulging and for one reason or another it isn't stable at 133mhz fsb (could be those caps... my memory.. or even a rinky dink power supply i'm using). It is also limited to a max multiplier of 12-12.5.. unless you add wires into the socket (called a wire-mod). Aside for those short coming it is a great board and just an awesome retro platform. It supports the Voodoo's, has a good ole ISA slot, and is faster than any P3 and will give most low to mid range P4's a run for their money. With some patience and the right chip, you could clear 2ghz on it. Initially this board did have some issues as far a as a buggy IDE controller and poor PCI performance.. but I have never had any problems with it while using the right set of VIA 4-in-1's. Unless someone out there would like to prove me wrong, this board (or its Abit equivalent K7A) is the fastest Athlon with an ISA slot.

Thank you guys!