Use ATX PSU With HP Proprietary Motherboard (Add a GPU) REVISED & Simplified

This is the 3rd revision of the project. This greatly simplifies the wiring & helps address some of the issues other users have reported.

Many newer HP Desktops come with a proprietary PSU & Motherboard. These PSU's are often low wattage leaving little room for system expansion. A higher wattage PSU can be purchased but are expensive & still limited. A PSU upgrade will allow a more powerful Graphics Card (GPU), extra hard drives, & more in your system. It even can replace a broken one on the cheap.

Many of the HP desktops can be booted with a standard ATX PSU but it requires the ATX PSU's green wire to be always grounded, resulting in the PSU always running. This is fine for many, but can cause issues. Luckily this can be fixed by following this guide.

This guide will only work with HP PSU's that used 2 x 4 Pin(CPU Power style) connectors for power & a 7 pin connector for the motherboard. Does not matter how many of the 7 pins are used, any configuration will work. (See Step #2). This will NOT work with 6 pin HP power supplies

Confirmed Compatible PSU Models:

D16-180P2A*

PA-3401-1

DPS-310AB

D19-180P-1A*

*= Personally Confirmed

There are a few ways to build the adapter. Most pieces can be substituted depending upon your requirements.

Materials:

1: PSU:

1. ATX, TXF, Flex ATX, Pico PSU, etc. As long as follows ATX standard with a 20 or 24 pin connector.
2. Minimum 2 amps on 5v VSB rail. Not a problem on modern supplies.
3. Look for one with hefty 12v rail(s). The entire PC will be powered off 12v. If using a GPU this is extremely important.

2: Boost converter:

1. Needs to support 5v input & 12v output. Minimum 2 amps output.
2. MT3608 & Xl6009 are common choices.

3: 4-Pin CPU Power extension cable:

1. Needs to reach from adapter board you are making to 4_Pin_#1 connector.
2. Only need the male end. Any cable with a male 4 pin CPU connector will work. Can cut off the original HP PSU.

4: Relay module:

1. Either 5v or 12v. 5v is preferred. This tutorial will show both options.
2. Common relay modules are rated at 10 amps. 10 amps is plenty.
3. This tutorial will use a 10 amp relay for 5v descriptions(Red & Blue) & a 30 amp relay(Green & Blue) for the 12v. This is not required, just used to keep things organized.

5: ATX Female plug/board

1. Any female ATX plug(Same end as a motherboard).
2. An extension cable is easiest.
3. I used one a "Dual power Supply Sync Adapter". (Search that)
4. Be cautious with ATX breakout boards as they do not always break out the required 5v VSB line.

6: 1 Schottky Diode

1. 1 amp rating minimum

7: 1 Resistor

1. Value depends upon your PSU & Motherboard
2. See Step #10 for resistor calculation/size
3. 1/4 watt minimum

8: 1000uf capacitor (or larger):

1. Value is not critical. I found 1000uf to be the minimum required for an Elite Desk 800 G3
2. Some machines may require a larger value. Adding a GPU may require a different value.
3. 16v minimum.
4. Many users report this as unnecessary. Your experience may vary.

9: Header/Dupont wires:

1. The correct header is a ST PHR-7 2.0 plug
2. Dupont connectors will work. Need a minimum of three wires/conductors.
3. You can cut the original one off the HP PSU (PWRCMD).

10. Wire:

1. I used 16 AWG for the 12v, ground, & 5v VSB. 22awg for everything else.
2. Thicker is better for 12v Power, Ground, & 5v VSB. Other lines are okay with a smaller gauge, but don't skimp.

11: Mounting Block & Screws

1. You will want to secure the components down. I used a piece of wood. Anything NON conductive will work.

Tools:

1: Small Screwdrivers:

1. The relay has small screw blocks. A small Philips or flat headed screw driver is needed.

2: Wire Strippers/Scissors:

1. Someway to strip & cut the wire to length.

3: Solder Iron & Solder:

1. Solder the connections.
2. Can be avoided if purchasing all components with screw blocks &/or splicing.

4: Multimeter

1. Never hurts to check things & debug.

To make this tutorial easier, here is a breakdown of the terminology that will be used.

Adapter Board = The adapter made in this tutorial.

Connectors:

PWRCMD Connector = 7 pin connector on the HP motherboard. HP PSU Connects to it. Not all PSU's use all 7 pins. Some only have 3 positions populated.

4_Pin_#1 = 4 Pin connector closest to the PWRCMD connector. Location varies depending on motherboard. Typically is closest to the PSU, HDD Power Header, & SATA Ports.

4_Pin_#2 = 4 Pin connector closest to the CPU. Sometimes is under a plastic fan shroud. Location varies depending on motherboard. Typically is closest to rear IO ports.

Wiring:

ATX PSU:

PS_ON = Green wire on ATX PSU that turns on PSU when connected to ground.

PWR_OK = Grey wire on ATX PSU that tells PC the Power supply is started up and ready.

5V_VSB = Purple wire on ATX PSU. Supplies 5v to the PC even when powered off. Used for motherboard power on circuitry & USB port charging when off.

HP Motherboard/PSU:

PWR_ON = Green wire on HP PSU that motherboard uses to power on. Is 3.0 - 4v when PC is off. 0v when PC is on.

PWR_ID = Grey wire on HP PSU that motherboard uses to ensure PSU is started & ready. Required to boot.

FAN_TACH = White wire on HP PSU. Used by the motherboard to control the PSU fan. Not present on all systems. If present will need to be bridged to a fan TACH pin (see Step #6)

Electronics:

NO = Normally Open. Terminal that is not connected to output by default. Becomes connected when signal is applied.

NC = Normally Closed. Terminal that is connected to output by default. Becomes disconnected when signal is applied.

COM = Common. Terminal that either the NO or NC terminal gets connected to depending upon signal.

Relay #1 = Relay that switches between 12v Boost Converter & ATX PSU 12v rail when HP motherboard is powered on.

The original HP PSU is always outputting 12v to the two 4 pin connectors. This is the equivalent of keeping the green & black lines on an ATX PSU jumped.

When the power button is pushed the motherboard pulls pin #4 (PWR_ON) of PWRCMD connector LOW. Pin stays LOW until the PC is shut off or power is lost. It then returns to HIGH.

Pin #3 (PWR_ID) of the PWRCMD connector is the equivalent of ATX PWR_OK. If the line is never OK (HIGH) the PC wont boot. This wire can be connected to a constant 12v source via a resistor. Resistor value varies depending upon original PSU model. Try around 100K Ohm to start. See Step #10 for more details

The pins on the PWRCMD connector are:

#1 Ground (Black wire)

#2 PWR Meter (Purple wire)

#3 PWR_ID (Grey wire)

#4 PWR_ON (Green wire)

#5 Ground (Black wire)

#6 Fan_Tach (White wire)

#7 Fan_CMD (White & red striped wire)

Not every PSU uses all the pins. Some only use 3 (GND, PWR_ID, PWR_ON). I have not found any issue leaving PWR_METER & Fan_CMD disconnected.

How this project works:

The relay is powered off the ATX 5v_VSB line. Directly for a 5v relay & via the boost converter for a 12v relay.

The ATX PSU PS_ON wire is connected to the HP PWR_ON wire via a diode. Diode cathode is facing motherboard PWR_ON pin.

The HP PWR_ID is connected to the boost convertor 12v output via a resistor.

Relay #1 has the COM terminal connected to the 12v pins of the 4_Pin_#1 connector on the motherboard. The NC relay terminal is connected to the boost converter 12v output. The boost converter input is connected to the ATX 5v_VSB. The NO relay terminal is connected to the 12v line of the ATX PSU. The capacitor is connected in parallel with the NO terminal. The relay triggers on a signal from any 5v line on the ATX PSU(Not the standby).

The boost convert supplies constant 12v to the 4_Pin_#1 connector. When the power button is pressed PWR_ON is drawn LOW, which brings PS_ON LOW, which switches on the ATX PSU. Once the PSU is on it triggers relay #1 which connects the ATX PSU's 12v lines to the motherboard, cutting off the boost converter. A small interrupt of power occurs which is minimized by the capacitor.

To use a dual power supply adapter for the female ATX plug solder it like the above image.

You could also use an ATX extension cable or a Complete ATX Breakout Board. Those will not require any soldering. Just splice or use the screw terminals.

Wiring is simple. Follow the above images for guidance.

Diagrams are all the same concept. They are just tweaked for both 5v & 12v relays.

I made many revisions to my adapter. Some images may contain slight inconsistencies due to improvements. Please notify me of any errors.

1. Make sure PSU is unplugged from AC Mains.

2. Plug the 4 pin or half the 8 pin(4+4) CPU connector into the 4_Pin_#2 connector.

3. Plug the 4 pin connector from the adapter board into the 4_Pin_#1 connector.

4. Connect the ATX PS_ON pin to the PWR_ON pin on the PWRCMD connector via a diode.

5. Connect PWR_ID on the PWRCMD connector to the boost converter 12v output via a resistor.

5b. Connect FAN_tach pin on the PWRCMD connector to the corresponding fan pin(if needed).

6. Connect the 24 pin ATX connector of the ATX PSU to the adapter board.

7. Attach any 6/8 pin connectors to GPU & any Sata/Molex connectors to HDD/SSD's.

8. Plug the PSU into AC Mains

9. Press the motherboard power button

The PC should power up! Success!!? If not see Step #7 Debugging.

On some HP PSU's the fan is used as a system fan. Without this fan connected the PC will throw error 90E.The PC will still boot but the error is annoying.

An easy way to tell if you need this fan modification is to see if there is a wire in position #6 (Fan_Tach) on the PWRCMD connector. If so this modification is needed. The example Elitedesk 800 G3 requires this fan mod.

The PSU fan communicates with the motherboard via Pin #6 (Fan_Tach) on the PWRCMD connector. This pin is looking for a fan Tach signal. There are a few options:

1. Run a jumper wire from a different fan in the PC's Tach pin to the Fan_Tach pin. Any fan even the CPU will work.

1. Rig up a fan. Tie into the ATX PSU 12v & Ground to power the fan. Connect the fan's Tach pin to the Fan_Tach pin on the PWRCMD connector. Note: Fan will always run full speed.

1. Add a fan controller. Connect one of the controllers Tach pins to the PWRCMD Fan_Tach pin

1. Add a Tach controlled fan to the ATX PSU. Remove the original fan from the ATX PSU & swap in a 3 or 4 pin fan. Run a wire outside for the Tach connection & connect to the PWRCMD Fan_Tach pin.

Both 3 & 4 pin fans will work. On a 4 pin fan the PWM pin will remain unused.

CAUTION: Be careful if opening an ATX PSU. Dangerous voltages are present & lethal.

Attached Videos demonstrate some common issues.

PC tries to boot but immediately powers down:

1. Make sure all wires are connected and connectors fully seated.
2. Ensure 4_Pin_#2 is connected.
3. Ensure PWR_ID wire is connected.
4. Try a larger value capacitor.
5. Try no capacitor.
6. Confirm the boost converter is set to 12v output. If using a 12v relay it may not fully trigger on a lower voltage. (See Relay Won' Trigger)
7. Try thicker wire.

Relay keeps triggering/relay light flashes:

1. Double check all wiring.
2. Ensure all wires are connected correctly & securely in the PWRCMD connector. Reversed wires are common.
3. Is a capacitor connected? If so, try it without.
4. Try a different capacitor value. This is how I found 1000uF to work for me.

Relay Won't Trigger:

1. Ensure the correct voltage relay(5 or 12v) is being used.
2. Ensure wiring is correct for the chosen relay type.
3. If using a 12v relay the SIG pin may need to be swapped to a 12v source rather than a 5v. (See last image)

Red Light on HP Power Button:

1. Power supply is not providing enough power.
2. Are PWR_ON & PWR_ID reversed?
3. Boost converter can not supply enough current. Try a different on or step #9
4. Try a PSU with a larger 5v_VSB current.
5. Check all wiring and connections. A loose/missing 4_Pin_#2 connector is common.

PSU Fan Running Full Blast:

1. Check to see if Fan_Tach pin on the PWRCMD connector is connected. Fan runs full speed without.

Note:

Some Ancient ATX PSU's will not work properly without a load on the 5v rail. Most modern supplies do not require this!! A motherboard typically loads this rail, but the adapter in this guide will not. A dummy load such as a 10 (or 5) ohm, 10 watt resistor or an incandescent automotive style light bulb may be used.

Motherboard & relay lights flashing, CPU fan spinning briefly(Pulses):

1. Check if PWR_ID Wire is disconnected
2. Check if PWR_ID & PWR_ON connections are reversed.
3. Disconnect the capacitor.

1. Issue with the 12v boost converter current. Try the following:

1. Unplug the ATX PSU from mains
2. Disconnect the 12v output of the Boost Converter from the rest of the circuit
3. Plug ATX PSU into mains
4. Connect the 12v output of the boost converter to the rest of the circuit.

If it boots, you will need an alternative way to supply the 12v standby.

Motherboard & Relays Power on briefly then quickly power off:

1. PWR_ID pin not connected/not correct voltage
2. Change PWR_ID Resistor value
3. Try disconnecting the capacitor
4. Try a larger value capacitor.

Everything worked until I added a GPU:

1. Try disconnecting the capacitor
2. Try a larger value capacitor.
3. Try a powered ATX riser. (Uses Sata, Molex, or 6 Pin). Some motherboards may limit PCIE slot wattage.

If it boots with the riser installed congrats. Unfortunately the PCIE slot wattage can not be changed. Your stuck with a riser.

Everything works until randomly powers off:

Power or heat issue:

1. Ensure you have adequate cooling & airflow.
2. If you bypassed the fan error (Step #6) additional airflow in the case may be needed.
3. Try a larger wattage PSU. The entire PC is powered off the 12v rail unlike a regular ATX motherboard. This requires a lot of current, especially if a GPU is installed.
4. Try moving any HDD/SSD to the ATX PSU connectors. The HP motherboard converts 12v to 5v for the SATA power connectors. By connecting the HDD/SSD's to the ATX PSU directly the 12v rail load is reduced.

Most issues I find result from low current on the boost converter 12v standby. This is due to a low 5v_VSB rail current. Here is a way to eliminate that as a potential issue:

You will need:

1. Adapter board (from this tutorial)
2. 12v power supply. 2+ amps. Make sure is a regulated 12v. The OEM HP PSU will work.

1. Unplug the ATX PSU from the mains power.
2. Disconnect the boost converter from the circuit.
3. Connect the Ground of the 12v power supply to the ground of your adapter.
4. Connect the 12v positive of the 12v power supply to where the output of the boost converter was connected.
5. Plug in the ATX PSU & the 12v Power supply.
6. Press the power button on the motherboard

You are essentially replacing the boost converter with a separate 12v source.

If it boots it means the issue is related to the 5V_VSB & boost converter. if not, continue through the debugging.

If using the OEM HP PSU, the yellow wires are 12v, the black Ground.

To boot the HP Motherboard from an ATX PSU without the adapter board:

1. Plug in the 4 pin (or 8(4+4)) CPU connector to 4_Pin_#2 .
2. Connect 12v & GND lines from the ATX PSU to the 4_Pin_#1 connector
3. Connect the ATX PS_ON & GND with a jumper.
4. ATX PSU will always be on. Needs to be unplugged to power off. HP motherboard should work as intended.

Thank you to user Kapuninja for your submission on using a resistor for the PWR_ID pin. This is the best way as it is how the OEM supplies work.

Below are some power supplies & their corresponding resistor values.

HP PSU Model: OEM Resistor Code: OEM Resistor Value: Adapter Tested With:

D16-180P2A 57D 383K ohm 380K ohm

D19-180P1A 86D 786k ohm 750K ohm

HP Z2 G4 PC was tested & confirmed working with a 100K ohm resistor. PSU model is unknown.

Your resistor may vary depending on PSU. If so, please comment so I can add it to the list

If you can not get it working, I had luck connecting the ATX PWR_OK to the HP PWR_ID pins. These are different voltages, so be careful.

Extra Info:

1. The 12v lines used to power the adapter board can be taken from any plug on the ATX PSU. I used the ATX connector but you can use any Sata, Molex, 6 or 8 pin.

1. I designed my adapter board to fit & mount in the 2.5" HDD bay. You can mount yours wherever.

1. The Molex & Sata wires from the ATX PSU can be used for storage drives eliminating the need for HP's proprietary cable.

Some Ideas:

1. Make a custom PCB to minimize the mess.

1. Make it with some transistors. A much better idea then a relay.

1. See attached pdf for voltages present on PWR_ID Pin (Useful info)

Pico PSU:

A PicoPSU can be used. Make the adapter according to this guide except instead of a boost converter; connect the 12v input from the PicoPSU to where the boost converter output would go. Great for a PSU replacement without modifying the case.

Special Thanks to users Kapuninja & mr reman for their contributions!

The original design & circuit is 100% original. Pinouts & functionality were discovered by disassembly & probing of the original HP components. No 3rd party was involved.

Many images were taken by me. Those not are from the following sources:

ATX PSU:

https://www.computeralliance.com.au/power-supplies

HP White Desktop:

https://www.hp.com/us-en/shop/pdp/hp-pavilion-desktop-tp01-3025t-bundle-pc

HP Elitedesk:

https://www.amazon.com/HP-EliteDesk-800-G3-DVD-Writer/dp/B01N27S6NF

Dupont Wires:

https://www.rexqualis.com/product/120pcs-multicolored-dupont-wire-40pin-male-to-female-40pin-male-to-male-40pin-female-to-female-breadboard-jumper-wires-for-arduino-raspberry-pi-2-3/

Capacitor:

https://www.amazon.com/5pcs-1000uF-Electrolytic-Capacitors-11X18/dp/B07GCV44GM

Solder Iron:

https://www.temu.com/8pcs-digital-display-80w-electric-soldering-iron-kit-180-450-degree-adjustable-adjustable-temperature-button-for-electronic-diy-kits-with-5-tips-solder-wire-tip-cleaner-g-601099522270700.html

Screw Drivers:

https://i.ebayimg.com/images/g/x1QAAOSwGqtjxGly/s-l1200.jpg

Scrap Wire:

https://png.toolxox.com/pngi?p=wTioxo_wire-png-electrical-wire-clip-art-transparent-png/

MultiMeter

https://www.superiorelectric.us/superior-electric-t3000-digital-multimeter-ac-dc-volt-test-volt-ohm-meter-vom

Wire Strippers:

https://www.lowes.com/pd/IDEAL-Wire-Strippers/3370008

Pico PSU:

https://www.amazon.com/Mini-PicoPSU-150-XT-DC-DC-power-supply/dp/B0045WFZSQ

3 vs 4 pin fan diagram:

https://www.cgdirector.com/3-pin-vs-4-pin-pc-case-fans/

PCB:

https://www.wevolver.com/article/trace-pcb-a-comprehensive-guide

ATX Breakout Board:

https://www.ebay.com/itm/224599257814

ATX Extension Cable:

https://www.amazon.com/StarTech-8-Inch-Power-Extension-ATX24POWEXT/dp/B000FL60AI

HP 7 Pin plug:

https://superuser.com/questions/1713585/how-did-hp-made-their-power-on-bottom-work-with-no-vsb-standby-on-their-pro-29

HP 3 Pin Plug:

https://h30434.www3.hp.com/t5/Desktop-Hardware-and-Upgrade-Questions/Power-Supply-Upgrade-for-an-HP-590-P0033W/td-p/6987299

ATX PSU Plug:

https://www.lifewire.com/atx-24-pin-12v-power-supply-pinout-2624578

Circuit schematics: Fritzing & draw.io.

Hope this has helped out! Feel free to modify/tweak as needed.

Please leave a comment with any questions/suggestions. Will do my best to help.

Additionally, if you know models of HP Motherboards & PSU's this adapter works with please comment so I can add them to the list.