This is not for the feint of hart, and you are dealing with high currents, and potentially high voltages. If you don't know what you are doing, don't do it. Back story.. I have about 6 HP DL360 and DL380 G8 servers, each comes with 2 power supplies. They vary from 12v 40A to 12v 60A. I only run one PSU in each machine otherwise I end up with a monstrous power bill.. So.. what can you do with the extra PSUs.. well, you can hack them into being a generic PSU. These PSUs can be bought on amazon and ebay pretty cheaply, between $20 to $30. They are high quality, and designed to operate 24/7 for years at a time. They are also pretty much useless outside of an HP server (which is why they are cheap) There are a ton of videos on youtube (search for "hp server psu modification") on how to perform the modification. With a little bit of heavy gauge wire and soldering, and a few resistors, you can run them outside the server. I went with a little more elegant solution, for $10 each I bought 3 (except I only received 2.. waiting on the 3rd) of these card slot adapters that people make for bitcoin mining rigs. To get anything more than 12v, you have to connect them in series. To do this, 1 remains unmodified, the subsequent ones must have their chassis isolated from ground to prevent short circuiting. The circuit board remains connected to ground via the power supply cable. You can stack a few, but I would not go past 36 or 48V (so max maybe 4) before you will exceed the power capabilities of the circuit boards. To go above 48, use a DC booster. This is my test setup with the booster which is configured to 48V (keep in mind, boost the voltage, drop the current, there is a calculation). To bridge them into series, I used a pair of 12awg wire (effective awg of combined wire is 9awg, more than enough for 40A). I will place a third in the series when I get the 3rd adapter. Why am I doing this.. because I bought new external drivers that are 36v to 90v, and high voltage PSUs can be pricey, and since I already had the high quality server PSUs, might as well use them). I'll start a separate thread int he builds forum of my upgrades overall later once I figure out how to wire everything up into a box.
