Update to 144.0.0.0.0 BootROM and test with a clean install, preferably on a new drive. Install DriveDX and check if you don't have any problems your old ones.Hey Alex,
The CPU boot tray arrived and it has been installed. it came with 16GB of OWC RAM (4 x 8GB) in slots 1-4. I replaced it with 48 GB of OWC (3 x 16GB) in slots 1-3. I picked up that RAM from OWC during a RAM price dump several years ago. The system boots....YEAH !!! Your diagnosis and remedy where right on!! Thank you!!!
Here are the system preferences:
macOS High Sierra v. 10.13.3
Mac Pro (Early 2009
Processor 2.93GHz Quad-Core Intel Xeon
Memory 48 GB 1066 MHz DDR3
Startup Disk MacPro SSD
Graphics NVIDIA GeForce GT 120 512 MB
Serial number H*****L**PD
Hardware Overview:
Model Name: Mac Pro
Model Identifier: MacPro5.1
Processor Name: Quad-Core Intel Xeon
Processor Speed: 2.93GHz
Number of Processors: 1
Total Number of Cores: 4
L2 Cache (per Core): 256 KB
L3 Cache: 8MB
Memory: 48GB
Processor Interconnect Speed: 4.8 GT/s
Boot ROM Version: MP51.0084.800
SMC Version (system): 1.39f5
SMC Version (processor tray): 1.39f5
Serial number system: as above S/N
Serial number (processor tray): ******************
Hardware UUID: *********************
However, it boots very SLOWLY................. I have reset the PRAM, changed the CMOS battery, uninstalled ESET Cybersecurity. It is getting better, but seems that it wants to work faster, but seems "bogged down" and very slow. I am slowly getting to the point where the spinning color wheel is always appearing.
I think that I have a lot of programs running that I don't use anymore, like ESET. What a power sucker....I have the impression that I have to uninstall some programs. Your thoughts would be appreciated..
Thanks again,
boomer
MP5,1: What you have to do to upgrade to Mojave (BootROM upgrade instructions thread)