Mine has a phenom 2.5 and is running iatkos 10.6.3 very nicely using an nvidia 9500 gt card. I installed with just via chipset (supervia i believe it is) and nvenabler and I use NO NETWORK DRIVER at all and it detects my SMC gigabit card. the internal one is realtek 1000 or 8169 driver I believe but try no driver first because that may work. If i put in a realtek driver (either one) it detects card b ut doesn't connect to internet at all. in reg leopard 10.5.8 i used realtek 1000 driver, but discovered the no driver trick for Snow Leopard and have used it on other machines with realtek cards/chips. I can't seem to get 64bit to work though and I'm not sure why... (anyone have this MB working at 64 bit out there?) but with Quartz Extreme and 4 gigs ram, it's pretty damn fast! I also have a pentium Duo Quad machine running same drivers except it's intel chipset (same graphics same sound chip) and it runs 64 bit no problem. Best way to see if a MB will be 64 bit is just install chipset and nvenabler drivers first and see if it comes up in 64 bit. then add drivers one at a time for sound and network and check to see if still booting 64 bit.

Good luck!