Fuel XIO Voltage - Printable Version

Fuel XIO Voltage - Printable Version

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Fuel XIO Voltage - cz7asm - 02-23-2021

Hi,

my "new" Fuel shows problems with XIO 5V rail - it reads no voltage after PSU power up and starts 30s auto power-down. Does anyone know if this voltage rail is monitored by one of those DS1780 chips and which one it might be? My guess would be the one on the graphics card. I wonder whether this is really a bad voltage rail or a faulty monitoring chip so I'd like to locate it and measure the voltage and perhaps try to replace the chip.

I also noticed an ALERT about PS fan not spinning but this is actually true - it's not. Another thing to tinker with...

Thank you for any hints.

Code:
Environmental monitoring is enabled and running.

Description    State       Warning Limits     Fault Limits       Current

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

           12V    Enabled  10%  10.80/ 13.20  20%   9.60/ 14.40   12.12

        12V IO    Enabled  10%  10.80/ 13.20  20%   9.60/ 14.40   12.19

            5V    Enabled  10%   4.50/  5.50  20%   4.00/  6.00    5.10

          3.3V    Enabled  10%   2.97/  3.63  20%   2.64/  3.96    3.35

          2.5V    Enabled  10%   2.25/  2.75  20%   2.00/  3.00    2.46

          1.5V    Enabled  10%   1.35/  1.65  20%   1.20/  1.80    1.47

        5V aux    Enabled  10%   4.50/  5.50  20%   4.00/  6.00    5.12

      3.3V aux    Enabled  10%   2.97/  3.63  20%   2.64/  3.96    3.27

PIMM0 12V bias    Enabled  10%  10.80/ 13.20  20%   9.60/ 14.40   12.19

     Fuel SRAM    Enabled  10%   2.25/  2.75  20%   2.00/  3.00    2.51

      Fuel CPU    Enabled  10%   1.44/  1.76  20%   1.28/  1.92    1.62

    PIMM0 1.5V    Enabled  10%   1.35/  1.65  20%   1.20/  1.80    1.49

PIMM0 3.3V aux    Enabled  10%   2.97/  3.63  20%   2.64/  3.96    3.27

  PIMM0 5V aux    Enabled  10%   4.50/  5.50  20%   4.00/  6.00    5.10

  XIO 12V bias    Enabled  10%  10.80/ 13.20  20%   9.60/ 14.40   12.12

        XIO 5V      Fault  10%   4.50/  5.50  20%   4.00/  6.00    0.00

      XIO 2.5V    Enabled  10%   2.25/  2.75  20%   2.00/  3.00    0.00

  XIO 3.3V aux    Enabled  10%   2.97/  3.63  20%   2.64/  3.96    3.32

Description    State       Warning RPM  Current RPM

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

FAN 0  EXHAUST    Enabled          920         1219

FAN 1       HD    Enabled         1560         2185

FAN 2      PCI    Enabled         1120         1502

FAN 3    XIO 1    Enabled         1600         2321

FAN 4    XIO 2    Enabled         1600         2117

FAN 5       PS     Active         1600            0

                           Advisory   Critical   Fault      Current

Description    State       Temp       Temp       Temp       Temp

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

NODE 0            Enabled   60C/140F   65C/149F   70C/158F   25C/ 77F

NODE 1            Enabled   60C/140F   65C/149F   70C/158F   23C/ 73F

NODE 2            Enabled   60C/140F   65C/149F   70C/158F   22C/ 71F

PIMM              Enabled   60C/140F   65C/149F   70C/158F   25C/ 77F

ODYSSEY           Enabled   60C/140F   65C/149F   70C/158F   22C/ 71F

BEDROCK           Enabled   70C/158F   75C/167F   80C/176F   25C/ 77F

RE: Fuel XIO Voltage - Raion - 02-23-2021

If the 5V rail is actually reading something while the system is on (tape a multimeter probe to it!) then you can be assured the Dallas Chips responsible for ENV monitoring are going bad. Which one? who knows, it's usually the one on the mainboard that fails.

Whatever you do, get the chip fixed, don't turn off ENV monitoring and run the system that way or you will cook your graphics card in short order. We've had people do this and apparently the env monitoring for fuel is responsible for scaling up the fans when the system is running.

RE: Fuel XIO Voltage - weblacky - 08-19-2022

Late to the party, but just for everyone else. I proved in my Fuel repair thread (https://forums.irixnet.org/thread-3185.html) that ALL XIO ENV voltage readings come from the DS1780 IC on the graphics card, removal of the card will show a lack of readings in ENV listing as proof.

So bad or null readings are the graphic cards fault (unless there really is no voltage, then it's the PSUs fault :-)

Voltages are not generated "on card", they are simply read from XIO slot on mainboard, I don't see any real VRMs on these graphic cards, they take voltage directly from a PSU rail, via XIO slot.

Cheers!

RE: Fuel XIO Voltage - weblacky - 01-13-2023

Hi All,
Correction to my above statement. There is of course at least one VRM onboard but it’s not 3.3v or 5v as those definitely appear to come from the PSU, through the XIO slot (card edge connector directly has connections to 5v and 3.3v test points, same rail the graphics DS1780 is connected with. However it’s possible the XIO 2.5v is generated onboard the graphics card.

I’m currently in a private conversation with another member about troubleshooting this rail and they’ve confirmed a card swap resolved the issue.

So that would heavily (but not conclusively) lean towards internal generation instead of external generation with overload by that one card. But it’s not 100% conclusive yet.

Currently I’m thinking the main GPU VRM portion on the card may be the XIO 2.5v rail. Not certain at this time, will update when I know more.