GS600 PSU not working in xw4600 Workstatio​n.

[Shad0w12]

I purchased a Corsair GS 600 - 600W power supply but, it will not power up my PC.

I tested the power supply using a paper clip test and it is working fine.

Issue: When I press the power button the all the fans spin for a brief second and then it turns off.

It seems like I am being hampered by the mother board being proprietary.

Is this the case?

And if so is there anything I can do to get around this?

Please advise.

[gabornico]

There is another disussion where this is explained.

The xw4600 uses a different pinout for the power connector.

I have done the modification but could not get it to work with my Corsair TX650V2.

[Skylarking]

Gabornico, as a suggestion, it's simpler to link to the docs on HPs web site rather than attach them to your post.

It's also much better to make it clearer to others what these docs actually are. If I had known they were HPs service and technical guides, I wouldn't have needlessly wasted my limited wireless download capacity fetching then '

Anyway, both guides you referenced agree though the 1st doc on page 159 has pins 12 & 23 as unused while the 2nd doc on page 164 has these pins allocated to +12V-D. No idea what +12V-B and +12V-D signify, maybe different supply circuits?

It's also worth noting that the standard ATX PSU has some differences, specifically:

ATX pin 12 = + 3.3V whereas HP uses this pin for +12V

ATX pin 20 = -5V (optional) whereas HP uses this pin for ground

ATX pin 23 = +5V whereas HP uses this pin for +12V

So, if you use a standard ATX PSU, you may damage the ATX PSU if -5V exists and is sent to ground by plugging into the XW4600. Likely there is no -5V these days so that not probably going to be an issue, so then it's just the ATX PSU supplying +3.3V and +5V whereas the mobo expects a +12V feed and somethings got to give in these situations.

Rewiring is a simple task and solves the 2 voltage differences. But, mind you, don't assume anything as the POK and PS-ON_L signals used by HP may or may not be the same logical level and timing as those used by ATX standard. These need some more investigation before one can be certain that they are compatible between the HP standard and ATX industry standards and may be the cause of the boot failures. If you have a CRO handy, you could check it out on a standard PC and compare it to a working HP workstation. Results could be interesting.

Anyway, this page on various PC power supply connectors is useful. Doesn't talk about POK and PS_Good signals and timing but I'm sure someone with more spare time can Google some info.

[gabornico]

I agree with you that linking to the guides would have been the best solution.

About  the three separate 12V rails: the first one is for CPU and RAM, the second one (12V-B) feeds the motherboard (PCI-E and other stuff) and the third one (12V-D) is for the drives.

My Corsair TX650V2 has only one 12V rail but it can provide up to 53 amps (636 watts).

I also have two older machines, a dc7700 CMT and a d530CMT both upgraded with that PSU.

It must be something with the PS_ON and POWER_OK because I tried double checked the wiring.

At the moment I neither have a xw4600 PSU nor a testing device so I took the built out one from the dc7700 CMT and underclocked the graphics card.

Looks like I will have to get a used one and find out if its wattage is sufficient for the Radeon 7870.

[gabornico]

after doing some research I´ve found a really interesting detail pic showing the mainboard plug of the stock PSU. The P_OK (pin 😎 is not connected. Pin 12 and pin 23 are empty too so it looks like there is no need to connect the 12V-D (this is for harddisks and optical drives) to the motherboard. So it´s time for some testing...

[Dan_WGBU]

gaborinico, the xw4600 power connector pinout picture is attached.  As you wrote, pin 8 is not attached (power OK generated from the power supply), and pins 12 and 23 are empty.  Additional +12V power is supplied by the 4-pin P3 connector (pins 1 and 2 are GND, pins 3 and 4 are +12V). 

I wonder why the Corsair supply can supply 53A at +12V, over 600W.  UL has some requirements where the total power from one rail cannot be greater than 240VA.  That is why HP splits up the +12V into several rails, to limit short circuit current and power, even through they are in the same connector.  Does the Corsair use one rail for +12V, or is it split up into several 'groups'? 

[gabornico]

Thanks for the schematic Dan.

The Corsair TX-series has a single +12V rail.

Since the last test also failed, there is only one thing left: the +5V.

HP xw4600 Delta Electronics DPS-475CB : +5,1 V

HP dc7700 CMT PSU: +5,08 V

Corsair TX-650V2: +5 V

[Dan_WGBU]

 Here is some more information on the xw4600 power supply.  This is not secret information, since it is printed on the power supply in the systems HP ships.  😉 

The xw4600 power supply has these rails:
 +5V  =  21A
 +12V CPU  =  15A;  This rail is connected to P3 pins 3 and 4.
 +12VB  =  17.5A
 +12VD  =  12A
 +5V aux (standby) = 2.25A
 +3.3V  =  15A
 -12V  =  0.3A
 Max on +3.3V and +5V combined  =  110W
  Max on 12V CPU, 12VB, and 12VD  =  34.5A
 Maximum continuous output  =  475W

   - PS_ON is the signal from the motherboard to turn on the power supply. 
   - POWER_OK is from the supply to the motherboard;  this is not used. 
   - PSU_ID is used to determine what size power supply is installed in the chassis, for some systems that have 2 different power supplies.  It is either not connected or grounded.  I don't think this will prevent the system from powering up, just make sure no voltage is connected to this pin 20. 

The +12V CPU rail is connected to P3 pins 3 and 4, and powers the CPU (obviously).
 
The +12V rail on main P1 power connector is either +12VB (17.5A) or +12VD (12).  I forgot exactly how +12VB and +12VD are connected, one is for the motherboard and one is only for the hard and optical drives. 

Disclaimer first:  I must give the standard disclaimer that any modifications or changes have not been tested, approved, or recommended by HP or anyone working for HP.  Any modifications will void the warranty and could damage the motherboard and other subsystems.  No one at HP can be responsible for any modifications or changes.  HP's official position is to get an HP replacement xw4600 power supply. 

Hacker's Hint, after disclaimers: 
   - How much +5V, +3.3V, and +5V aux (standby) current is available from the Corsair?  If they are less than what the xw4600 has, it could prevent powering up, especially if +5V aux is too low. 
   - Make sure the 12V pins on connector P3 can supply 15A.
   - Shorting PS_ON to ground (the paper clip test) should force the power supply to go on. 
   - With the supply forced on, what are the voltages on the P1 and P3 connector pins?     

The HP supplies you listed use ~5.1V for the 5V rail.  This is to compensate for cable losses, and makes the system more reliable.  I doubt this will prevent the xw4600 from powering up, though.  FYI.

[gabornico]

Thank you for your reply Dan.

What else should HP do than recommend its own replacement part at an exorbitantly high price of 136 Euro that doesn't even have two pcie connectors to fire up my graphics card.

This is my sixth hp desktop modding project, so -in most cases- I know what I am doing.

These are the other two of my "not recommended" hp desktop configurations:

------------------------------------------------------------------------------------------------------------------------

"Senior", music production, some older games

hp d530 CMT with Corsair TX650V2 power supply

- 3.2/1M/800 Pentium 4 Prescott processor

- CPU cooler mod

- Radeon HD3850 AGP graphics card with passive cooling mod

- 4 GB RAM PC-3200

- 120 GB S-ATA SSD, S-ATA DVD-RW

- silent fan mod

- customized Windows XP OS

------------------------------------------------------------------------------------------------------------------------

"Worker", stores all my data and does a lot more, running 24/7

hp dc7700 CMT with Corsair TX750V2 power supply

- officially unsupported Core 2 Extreme X6800 processor

- CPU cooler mod

- 8 GB RAM PC2-6400

- 64 GB SSD, 2x2TB HDD, DVD-RW, internal USB cardreader

- additional cooler for harddisk controller chip because this badass gets really hot an hp doesn't care

- silent fan mod

- 2nd serial port (Compaq Evo D510 spare part)

- Linux OS

------------------------------------------------------------------------------------------------------------------------

Thanks for the advice anyway.

Now let's get back to my "still-dont-want-to-work-station"...

The system board is a 2nd hand one that I put in a hp d530CMT case, so there is no warranty.

The first thing I did was to buy a 24-pin extension cable and modifying the wiring according to the pinout description in the xw4600 manual to keep the power supply compatible to standard systems. Then I built the ambient temperature sensor and added it to the front control panel connector.

Pushing the power on button turns the system on for approx. one second before it shuts itself down, so forcing the PSU should not be necessary. I use this method sometimes for testing PSUs with a dummy load but never tried this with a working motherboard. It would be great to know if it is safe to do so.

TX650V2 max current

+3,3V/25A

+5V/25A

+5Vaux/3A

+12V/53A (single rail)

-12V/0,5A

Voltages:

3,29V

5,04V @+5V

5,01V @+5Vaux

11,98 V

The xw4600 doesnt use the P_OK but I am sure there is a circuit somewhere on the system board that compares the three voltages against a reference at least once before proceeding to POST like the PSU does in a standard PC system.

[Dan_WGBU]

gabornico, I did not mean to question your technical expertise or knowledge, or the technical knowledge of anyone else on this forum.  I'm sorry if you felt that way.  However, as an HP employee, I am instructed to be very careful in my responses and to make very clear that any modifications are not approved by HP.  Most people on this forum are highly technical, know the risks, and will try modifications anyway, so that is why I am giving some (VERY unofficial) advice to try to help.  OK? 

I listed the xw4600 power supply pinout and current requirements so you can see if the Corsair matches the requirements.  It seems to match the HP supply.  You are correct, there is a circuit that compares voltages on the board before proceeding to POST.  The system board is shutting down the supply.  Connecting the Corsair should be simple, but something is missing.
   - Do you have the internal speaker and front panel LED connected?  If so, is there a pattern of beeps or LED blinks? 
   - Connector P3 provides the +12V for the CPUs.  If it is not connected, or shorted, then the CPUs will not be powered and the system will shut down. 
   - Try grounding pin 20 on the power connector.  (It will not cause any damage, but I do not think this will solve the problem) 

Other than this, I don't know why the Corsair would not work, unless it has some unusual sequencing between the power rails. 

It might not be safe to test PSUs by forcing the power supply on with a working motherboard.  If some of the voltages not not correct, it could damage the motherboard.  (this is why I am required to give a disclaimer, OK?)  If the supply is forced on, then the voltages at each pin on P1 and P3 can be measured.