At £7.79 from eBay I thought they were worth a punt and ordered one. I ended up converting three of them.
The specification for these are very impressive
i)
Designed to run at 12V at 63A at 100% duty cycle for 7 years without
interruption.
ii)
Unmodified can run at 12.5V
iii)
Modified can run at 13.8V at 50A (choose model carefully they are not
all easy to modify and do differ by model).
iv)
Fitted with over voltage, over current and over temperature protection.
v)
High quality construction.
Getting it up and running
There is plenty of info on the internet and will vary by model. This mod is for the HP HSTNS-PD18 the HP HSTNS-PL18 is different to modify.
13.8V modification (PD18 Version).
i)
Install a 1/4W 22K resistor from earth connection (4th
pin from left on bottom connection to LHS tab of variable resistor.
ii) I adjusted the voltage to 13.5V rather than 13.8V as it sometimes tripped on over voltage on start up.
Further info
Start mod info:-
https://makenotes.de/2020/04/turning-on-a-hp-dps-750rb-server-power-supply/
Voltage mod video
https://www.youtube.com/watch?v=tqDNg_HCvFk
Remember this is only for the HSTNS-PD18 version