Updating firmware n82
Eventually I got all the holes drilled that I thought I could get away with and the board is held securely clear of the base of the case.This is by far the hardest part of the job and even with all my careful measurement and drilling my expansion cards are slightly bent in their slots due to a couple of millimetres of misalignment. If I were to do this again I would probably drill wider diameter holes in the motherboard tray to allow a small amount of adjustment.It swallows the Z800 motherboard as if it were designed for it. I mentioned before that the motherboard mounting holes do not match up with the corresponding holes in the case’s motherboard tray.I had to drill and tap new holes for enough screws to hold the board safely with its heavy load of up to two CPUs with large heatsink/fans attached. Before starting I fitted a small random PCI card into the motherboard and used it to work out exactly where the board needed to be so that the cards lined up with their fixing holes on the side of the case.If you have the later 003 revision then you can use either X55xx or X56xx CPUs. It’s physically write-protected within the BIOS and does not get upgraded when you flash the BIOS.
Word on the HP forums is that the behaviour of an earlier revision flashed up to the latest BIOS and used with X56xx CPUs ranges from ‘works for me’ to ‘sometimes won’t boot’ to ‘total failure to POST’.
I have no way of knowing how much will actually be drawn by each rail so it’s safest for me to buy a single rail unit with a nice high overall amperage.
I plugged my prospective peripherals into an online PSU amperage calculator and it came out with a recommended 750W supply for dual 130W TDP processors, four 15K SCSI drives, an SSD and an ATI 7970 graphics card.
The main ATX power connector and the memory power connector are custom HP designs.
Thankfully the Z800 service manual gives the pinout of these connectors so it’s not hard to make up some custom cables to do the job.
The above image is taken from HP’s service manual for the Z800.