Powering an RX480 w/ a Pico PSU

[DarkKristen]

Hiya all!

 

I'm in the process of upgrading a used HP Z400 Workstation (Xeon X5690 - see full specs below) that I'll be using as a cheap rendering/ gaming rig. Only one problem, the 475W Delta PSU is proprietary for this particular HP model. I'm planning on using one (initially) and then eventually two Radeon RX480's (XFX 8GB OC Blower version). The 475 W PSU is going to be a tight squeeze for even one of these cards, it definitely can't power two of them.

 

My thought is this - I was thinking of using a picoPSU **only** to power the six pin connectors for the GPU's. With the updated drivers from last summer, reference cards are usually benchmarked drawing around 170W total. Subtract the 75W coming through the PCI-E slot and that leaves 95-100W via the six pin. A 250W picoPSU should (on paper anyway) be able to handle this -  I'd be drilling standoffs on the bottom of the chasis to mount the unit, as well as an add2PSU so the pico will power on the same time as the rest of the system. Just to be clear the picoPSU uses its own external 12V DC laptop style power brick, with that cable routing through a PCI slot blanking plate made to hold the DC input connector.

 

Thanks!

-Kristen 

 

Proposed Final Specs:

 

HP Z400 Gen 2 (6 DIMM slots)

Xeon X5690 6C/12T 3.4 Ghz base, software overclock (unless a modded BIOS is available to unlock overclocking- I know there used to be one, but the download link was broken.)

Corsair Hydro Series H75 with adapter to install the 120mm radator on 92mm fan mount

24GB (6 x 4GB) DDR3 1333mhz RAM

One (initially) then two XFX Blower Style 8GB RX 480 cards

500GB Samsung EVO 850 SSD

2TB Segate 7200rpm HDD

USB 3.0 PCI-E card

Windows 10 Pro / Fedora 25

 

[TheNuzziNuzz]

I think you should upgrade the PSU. I wouldn't trust it. Plus, and RX 480 requires a 500watt.

[DarkKristen]

1 minute ago, TheNuzziNuzz said:

I think you should upgrade the PSU. I wouldn't trust it. Plus, and RX 480 requires a 500watt.

Upgrading the PSU would definitely be my first choice, unfortunately the motherboard uses a proprietary connection and not a standard ATX 24 Pin. Adapters exist for the Z600 and Z800 workstations - but these two models use a different connection than the Z400, which I haven't found anything for apart from one person who rewired the traces on his Z400 MB - I'm down for some modding but rewiring traces is way beyond what I'm comfortable with.