We are seeing this exact same problem. When HP Supp Asst sugegsted v2.29 for the BIOS we went ahead and upgraded given the security references in the release notes. Now machines are taking forever to reboot. However, it *seems* to be related to having an external video card. The latest batch of 8200s we were deploying have add on AMD cards. When we took the card out? The restarts were normal.
v2.28 definitely does NOT have this issue. And as someone noted, the v2.29 update is one way - no going back.
I have a couple boxes in stock I can still mess with and one customer who got two new boxes we haven't put into service yet with the AMD cards still in them. I'm going to poke around the v2.29 BIOS and see if maybe there is something in there that can be tweaked to fix this. It's embarassing to have these great refurb boxes with new SSDs (makin gthem lightning fast) and a restart acts like it's dead.
What we've observed is the restart hangs on the power cycle. The screen is blank, power light is on and it sits there. Then you BRIEFLY see the BIOS post screen and the system boots normally. It's like the BIOS is hanging in the POST. I'm going to throw a diag card into one and see...
Anyone from HP have insights? These are very popular boxes and if people install v2.29, I have to think this problem will become more widespread.