Well it just goes to show you are never done learning in the IT business.
A few weeks ago I decided to deploy my backup web server as the primary was showing odd hardware errors in Server 2003.  However I couldn’t even get the backup to show me a POST boot.  In fact, it just stared at me with a red health LED on the front and nothing more.  The power supplies didn’t even light their green LEDs despite hearing the fans spin inside.  Inside the server showed only an amber Interlock light.
So I cold-booted the primary and brought it back online.  I pulled the backup DL 360 G3 and brought it home for the usual kitchen-table bench testing.  Yes, the wife just loves it when I do that.
But nothing I did resolved the seemingly dead server.  I reseated CPU’s, CPU power boards, RAM, power supplies and anything else that remotely looked removable.  Nothing.
I finally got around to ordering another backup DL 360 G3 last week off eBay.  It arrived today.  Finally, my anxiety of running live sites on a single box with no backup would soon be a thing of the past.  I unbox the new backup DL 360 G3, throw it too on the kitchen table and ………. nothing.  The EXACT same symptoms as the previous backup server.
So by the general laws of armchair logic, I knew this was no longer a problem with the hardware.  There has to be something else.  I hopped on Google, did the usual searches and spent a good 30 minutes reading post-after-post.  Finally, I found the answer.  Within 10 seconds I had both servers running great.
The problem is the recycler companies that buy these units up and sell them on eBay.  They don’t know HP units as well as they advertise.  And they DO NOT “test” them to ensure they boot.  At least they don’t AFTER they install two power supplies in a system specifically configured for a single power supply.
That’s right, the problem was the motherboard has a configuration switch (SW2 on DL360 G3) with 4 positions.  The 4th position specifically tells the system whether there are two power supplies or just one.  It’s not automatic in the G3 series.
The recyclers clearly acquired these units as single power supply, tested them, then loaded up the additional power supply under the assumption it would be auto-detected.  This isn’t true in the G3 series if the 4th switch on SW2 is not set correctly.  Toggling the 4th SW2 switch on the motherboard immediately eliminated the problem on both servers.
Now the power LED on each power supply lights up.  The Interlock light no longer lights up.  And the servers proceed to POST boot without a problem.
Hopefully this blog post will save somebody the headache and expense I’ve endured for such a painfully simple solution.