Is it safe to use the PSU from a Sun Ultra 40 to build a modern system?

I'm doing a new build in a Sun Ultra 40 case.

In that case, there's a built-in 1000W power supply.

Is it safe / ok to use that if I know that my draw would be fine with a new 650W power supply (a i7 6700k and a decent graphics card)?

Solution 1:

The power supply will not power the system because it lacks connectors required by modern systems. Furthermore, the motherboard will not fit in the machine without modification.

The Sun Ultra 40 workstation (service manual) uses the SSI EEB form factor. The motherboard sits on a tray that has a cutout for the I/O panel, so you'll need to cut the I/O panel protrusion out of the tray after removing the motherboard. Furthermore, the SSI EEB mounting holes are a bit different from the ATX mounting holes; even if you are able to mount an ATX motherboard onto the tray, three of the holes near the processor are different. This limits the system's ability to safely withstand a heavy processor heatsink/fan (HSF) assembly, so you'll need to use a smaller, lighter cooler, which may limit your ability to overclock.

More critically, page 7-6 of the manual (PDF page 156, shown below) indicates that the power supply doesn't have the required connectors. The power supply has proprietary connectors that fit on the edge of the original Sun motherboard; while the 24-pin main power connector does look like an ATX12V connector (judging from the image posted in Dan Neely's answer), there is no EPS12V CPU power connector. The hard drive connector is also nonstandard, intended for a proprietary backplane; there is no standard SATA or Molex hard drive power connector. The PCIe auxiliary power connectors may fit, but don't count on it.

Solution 2:

From my own experience with exactly that endeavour (wanting to re-use the attractive Ultra 40 M2 case for a regular PC) I can give you a heads-up, it will work. The supply can deliver about 750 Watts on the 12V rail alone, which is more than sufficient for the system you described. The "ATX-like" plug is actually ATX compatible, and Sun has stuck with the designated ATX colors. The thinner cable is used only for monitoring of fan speeds etc, and the PSU will start up just fine via the green pin power-on pin on the ATX plug However, for the harddrives and GFX extra power, you will need to build adapters yourself, or cut the extra power lead down and attach new plugs. If you have reasonable soldering skills, grab the power leads from an old normal PC power supply and fit it on the Sun ones, with good shrink tubes around the connections. Fitting a regular ATX mainboard is also quite some effort.. you will at least have to Dremel out the area on the back plate where the ATX cover plate will go, and add threaded holes for the mainboard stand-offs, since the original Sun backplate does not have anything near ATX-standard mounting holes. You're looking forward to quite a lot of electrical and mechanical handiwork, but you'll definitely end up with a cool looking PC when you're done.

Solution 3:

Safe? Maybe. Compatible? Chances are no. The service manual indicates a design with two independant power supply connectors, and a very different layout from what I typically see in a PC. If the pinout is ATX compatible, it'll be fine. I somewhat doubt it though.

The power supply should be able to power at least two video cards fine

The PCI configuration includes two supplementary power cables used for either the NVIDIA Quadro FX4500/5500 or the Quadro FX3450/3500 graphics cards. The connectors appear in FIGURE 5-18 and FIGURE 5-19

This thread talks about replacing the PSU (along with many pitfalls such as non ATX compatible mounts and an odd shaped PSU)

Taking into account that it uses SAS drives (which indicate its semi modern) and the motherboard tray isn't standard, If you already have the case do due diligence. You're really going to want to check things like model numbers abd connectors

Some lower end models did take standard parts but chances are this isn't going to be a simple matter of throwing in a standard motherboard and everything just fitting in.