Plug a power tapered pin into a square slot

[tienlp]

I bought an old HP PC (HP EliteDesk 800 G1 SFF) and want to change to a more powerful PSU for a dedicated video card (this PC uses a 240W PSU).

The problem here is, the motherboard doesn't use a 24pin power connector like other ATX motherboards, instead it uses (1) a 6-pin auxilary (2) a 2x2 connector, which I believe to be the same as the CPU connector and (3) a 3x2 connector as in the picture above. For the 6-pin auxilary, which is quite outdated, I can buy an adapter to convert 24-pin into 6-pin auxilary, the 2x2 connector is available on today PSUs, the only problem is the 3x2 connector

I was thinking if I can use the 3x2 connector on the PSU for this (which is for the video card), so I compared it to the 3x2 connector on the video card and realised they are nearly the same, the only difference is that the 5th pin on the video card is a tapered one, while the 5th pin on the mother board is square.

(photo borrow from a guy on the internet, the 5h pin is the bottom middle pin)

So what I wonder is
- Will a tapered pin fit a square slot ?
- If it fits, is there any problem if I use the video card power connector for the motherboard?
- And BTW what is that 3x2 connector for ? This PC doesn't have a dedicated video card (although it has 2 PCI-e slots), and I think the motherboard is powered by the 6-pin auxilary already ?

 

[Ubrales]

You need to get the proper pin-out layout from HP. This layout will describe the voltages used by the pins. Just because a connector will fit does not mean that the pin-out will match.

 

[Ironsounds]

Hello... +1^ Typically there are international/fed/state/local Power Wiring Color codes to help us without schematics.
Yellow +12vdc Red +5vdc black common etc. https://en.wikipedia.org/wiki/Power_supply_unit_(computer)

I would suggest a couple things in your endeavor.
1) ditch case and MB for a modern ATX PS style PC.
2) Connect your GPU power directly to the PS, not through the MB.
3) You can easily de-pin any kind of molex connector from the OLD PS connector and use it with the NEW one... for a perfect MB fit.

 

[tienlp]

What is that 6 pin (3x2) for ? If it is for the video card i can skip it and plug the PSU directly into the video card right ?

 

[ko888]

The HP EliteDesk 800 G1 SFF only uses +12V and -12V. Even the standby portion of the PSU outputs +12V.

 

[Ironsounds]

Hello... I can not say without my eyes there, or schematic... what ever Voltage That was connected to the MB AND if it came from the PS, then Wire the NEW PS/connector to supply it to the MB.

If all other Power inputs/connectors are accounted for, low voltage circuits, card slot voltage, AND IF?
1) I would try to boot first without the Video card for a Power/Smoke Test.
2) I would then try to Boot with the Video card powered to the PS.