Hello. I would like to try modifying a PC PSU to work in my PC (HP xw4600), but I have basically no experience with electronics. The only reason I am thinking of trying this is that my PC requires a proprietary PSU. To my knowledge, there is only one compatible model, and it is only 475W. Also, the only ones available are used/"refurbished". I want a PSU with more than 475W, and I would rather not buy a used one. Even if a used one is in good working order, who knows how much more life it has remaining? So, I've compared the pinout of a standard ATX/BTX PSU with the proprietary PSU my PC uses. Diagrams of the standard pinout are readily available online. I obtained the pinout for my PC's PSU from the "HP xw4600 Workstation Service and Technical Reference Guide". The image below shows the pins side-by-side, with the standard on the left. The obvious differences are on pins #12, #20 and #23. On pins #10 and #12, the standard is "+12 VDC". On the proprietary PSU, it's "+12 V-B". I searched for that on the Internet, but did not find an explanation of the "V-B". Below the image showing the pin configurations is some additional information from the service and technical reference guide for my PC that seems relevant.
My questions are:
- To modify the pinout on a standard ATX/BTX PSU, would I just need to remove pins #12 and #23, and get a ground into pin #20? If so, to get a ground into pin #20, can I create a new ground pin by soldering a piece of wire to one of the other ground wires? Is it okay to use one ground wire for two pins?
- What does the "V-B" in +12 V-B mean?
- In the "Maximum Current Per Rail" chart, it shows different maximum currents for different +12 V rails. Does that mean that the number of amps on each rail is proprietary as well as the pinout? Might a standard ATX/BTX PSU deliver more continuous current than is specified in the table?
- In the "Maximum Current Per Rail" chart, it shows +12 VCPU and +12 V-D. I assume the VCPU is for the CPU, but what does "V-D" stand for?
- Regarding the information in the "warning", is that to avoid damaging the motherboard or the PSU, or both? If I were to use a standard ATX/BTX PSU, it is possible it would deliver enough watts to damage the motherboard, or will the motherboard and other components only pull what they need?
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