I've had a single instance of a purple screen of death on the ASRock Z68 Extreme4, looks like the Broadcom is the likely cause Broadcom related PSOD. The ASRock Z68 Gen3 I've moved to uses Realtek instead, no PSODs seen so far.
2011-07-19 News Flash #2
ASRock "Fatal1ty Z68 Professional Gen3" seems to work fine, LSI VMDirectPathThru testing on ESX 4.1U1 and Windows 7 x64 natively all worked fine. No ESX PSODs. Although the dual Realtek NICs aren't recognized in ESX 4.1U1, install an Intel Dual NIC worked around the issue for me temporarily, and with the release of ESX 5.0 soon, we may wind up with native Realtek support anyway.
2011-07-18 News Flash #1
Folks, I got a dreaded PSOD today on ESXi 4.1 Update 1 when trying to do different VMDirectPath configurations, and I’m not sure why, here's the error:
“Recursive panic on same CPU”
It may have to do with my trying with Intel RST RAID and my 9260-8i LSI RAID Adapter tonight. Anyhow, don’t conclude this means anything significant, other than I need more time to obtain repeatable and reliable ESXi 4.1 Update 1 results. Such bumps in the road are inevitable, and it's not like I had any expectation I'd have any type of official support. Once I do work it all out, I'll document the entire setup procedure, starting with a video walk-thru of all configuration steps, from first power on and UEFI config (I have a frame grabber that'll handle recording it), showing the simple ESXi install (probably 5.0), configuring VMDirectPath, and finally creating a virtual machine with VMDirectPath.
All that said, I’m moving to a new ASRock motherboard tonight, the Fatal1ty Z68 Professional Gen3. My focus is really on preparing for vSphere 5.0 as soon as it’s released, with its >2TB volumes, USB 3.0, and Aero support. I also want to get my automated backup server virtual machine running soon (Windows Storage Server 2008 R2 Essentials). So I’m not sure how much more time I’ll have “playing” with the Extreme4, and/or ESX 4.1U1 this summer, so I may never figure out this particular PSOD.
But I do know that the nothing I’ve ever done worthwhile was ever easy, hope you'll continue to ride along with me as I continue to post new information at this site…