Hello all,
Thought I'd post my successful build here:
MB: ASRock X79 Extreme11 BIOS 2.20
CPU: Xeon E5-1620
RAM: Kingston valuram 4x8GB 1600 ECC
GPU1: Radeon HD 5450
GPU2: AMD FirePro V4900
OCZ Vertex4 used to test swap to host cache, WD Black 1T drive for VM datastore
Highpoint RU1144A card to pass single usb3 ports to VMs
This is running on ESXi 5.0.0 build 914586. I had to inject the nic driver into the ESXi image with ESXi-customizer. I've been really happy with it. Everything passes through (mostly) without issue to the windows 7/8/2012 VMs that I've built so far; I can give each vm over 2GB of ram with the pcihole trick. Youtube green screens on the 5450. Haven't tried linux yet, but plan to once I have some free time. The PLX bridge chips don't get in the way of GPU passthrough on this board.
I also have the LSI controller (reflashed with IT firmware) passing through to a FreeNAS vm without issue with 4x WD Red, 1x OCZ Vertex4 for cache, 1x PNY Prevail Elite for ZIL. I had to use E1000 nics because vmxnet3 is unsupported and I had weird issues using vmxnet2. Seat-of-the-pants performance is pretty good. Haven't had time to benchmark it yet.
The only thing I need to do now is figure out how to get Bluray playback to work for my htpc vm. PowerDVD doesn't want to run in a virtual environment.
-Jon