Nice Project, I build up my 5000 from spares 20 years ago, when parts were still cheap and availiable on ebay US.
The Proliant 5000 uses proprietary VRM modules as you allready noticed.
There are two additional VRMs needed for the motherboard.
Try to find CPU boards complete with CPUs, coolers and VRMs, its will be a long and stony road to find these seperate.
There are different memory boards for the 5000, the originals supported only buffered FPM DIMMS up to 128 MB, while the later supported buffered EDO DIMMs up to 256 MB.
2 memory boards are installed on the motherboard and memory is installed in quads.
The PS is right for the rack Version, the Tower version is different, seems to be the same as Proliant 4500, 4000, 2000, 1000.
The housing is mostly the same on these models no matter if the tower or the rack variant.
The power button is a simple switch on the black box, there is a plastic mounted on top to prevent accidental switching.
The black box has a second switch inside activated by a pin on the door, to prevent powering with door/top removed.
The 5000 supports standard Floppy but the CD-ROM is SCSI. (no motherboard IDE, but a IDE port on a plug in card i.e. on a soundcard should work)
CD-Rom should be Compaq branded to enable booting of the SMARTstart CD, or you will have to use floppy for configuration.
Smartstart 5.5 is the last release supporting the EISA models.
You will need the SCSI cage and the hot Plug drives as well.
A SmartArray controller was usually installed in these boxes.
Forgot to mention that the board will not start if the system fans are not connected, so these will be one more item on your list.
The Proliant 5500 (PPro Version, there is a 5500 quad Pentium II Xeon as well) is another quad PPro, but uses generic VRM modules and easier to find buffered EDO DIMMs might be another option.
https://theretroweb.com/motherboards/s/compaq … 0-5500r-p6-ppro
Full system: https://live.staticflickr.com/4023/4607198020 … 003951417_b.jpg
Mobo only: https://servers4less.com/007454-002-hp-system … er-refurbished/
Not sure if upgrading a proliant 3000 (the older 66Mhz Bus version with CPU boards, the later 100 MHz have the CPUs direct on the mobo) with PL5500 PPro CPU boards works?
I can look up the spare part numbers for the needed parts in the pocket reference manual if needed.
For the CPU boards I may have some spares , but they miss VRMs, CPUs and coolers.
But my advice would be to look for a complete system with only some CPUs missing.
I would give mine away, but unluckily I am on the wrong side of the pond and the box is heavy as hell.
Feel free to ask further questions, I got the 5000, the 5000R and the 5500 PPro, so you might call me an expert on these Compaq servers.