Who told you that? They do not sell that model now, but they are very much still in the retail motherboard business.
Apparently, P35 M/Bs are "obsolete." Mine has 5 Peripheral Slots. Boards I'm seeing on the Internet have 2 Slots. With Video Slot separate, and Sound on the M/B, I still need 3 - 5 Slots for Internet Cable or Wireless Card, Pinnacle PCTV, at least 1 Linux Hosting Tower, Other. Since no Firm's Liability Insurance Carrier will allow hire of Heart/Stroke Patients, I must try to set up a home-based business. I have four ready-to-market Screenplays I wrote, one of which a Producer wanted to buy. Sale requires Literary Agent. Agents aren't signing new Writer Clients at present. My other option is to build and possibly host websites. I learned how to do this by creating my own professional site, www.i-write-for-all.net, and hosting site www.i-host-all.net, which you are welcome to check out.
What will work? Any P35/P45 motherboard with a PCIeX16 video slot (that's nearly all of them) as long as you do not need 5 PCI slots.