PE2650 ESM

I have a PE2650, OS W2K server SP4, that has been running for five years with no problems.  Sometime ago, I noticed that the amber caution was lit steadily, the lcd is blank and when the server was started the infamous Embedded Server Management Error, Press F1.......dadada.   Another thing I noticed is that the fan speed seems to at max rpm and is very noisy.  After reading several posts about these various symptoms and performing a few updates, which I'll get into, there is still no fix.  Another symptom I noticed and has been mentioned in another post is within device manager I show three pci devices with no drivers (can't seem to find them either)  Anyway, I finally decided to order another riser card off ebay making sure it was the same part, i.e. P1743 PRINTED WIRING ASSY..., Riser, PowerEdge 2650, 533FSB.  I tried to install the riser this morning and the display lit up this time indicating a error E0276 Mismatch  VRM 2.  Also, the power button led just flashed. The server would not start.  I put the original riser back in the server came up. 

The server hardware/updates with the original riser installed are:

Intel(R) Xeon 2x CPU 2.8GHz
2G RAM
Bios A21 Successful
Dell PERC 3/Di RAID 5  FW V2.8.1 Driver 2.8.0
Installed Open Manage Server Administrator (OMSA) V 5.5

When I tried to install the esm update off the dell site ESM-WIN-A02.exe, I get an error stating that it is incompatible 
I did try an update that I saw on http://www.itoperationz.com/2010/02/poweredge-2650-esm4-error-embedded-server-management/ Also to no avail.
In fact I got a baseboard mgr not available.

All this led up to replacing the riser.  I am still pretty new to this server.  So, any direction would appreciated.  I believe that since the display did start working after inserting the new riser that might be the direction to continue in, but I am not 100% sure.  Thanks!