dual psu GPU or PSU causes crash | Wall PC

[KzE]

For two years I have been building a wall PC.

But now I have problems with the hardware and I am seeking your help since I seem to have tried everything and I have no solution.
The buildlog of the PC is here so you know how complex it is. You really should take a look there first:

https://linustechtips.com/main/topic/744224-wall-pc-build-log/

 

What’s the problem:

-         The computer boots normally and works fine without the GPU driver installed.

-         As soon as the GPU driver (EVGA GTX1080) is installed, the computer crashes either during startup or shortly after login, no error-code or bluescreen. Just black.

-         PC runs stable in safe-mode (where presumably the GPU driver is not active)

 

What I (and friends) have tried:

-         Replaced GPU driver with newest driver. Tried Nvidia as well as EVGA driver.

-         Replaced Win7 with Win10 (works until Win10 is online and updates drivers)

-         Updated Bios

-         Tried different monitor

-         Tried different monitor cables

-         Tried HDMI / DVI

-         Disabled on-board intel graphics

-         Tried RAM in a different PC to check if they are good, they are.

-         Tried different SSDs

-         Disconnected all non vital SSDs

-         Prime95 stress-tested CPU, all good

-         Tried all PCI-e Raiser cables by themselves and in combination, all good

-         Completely disconnected the two HD-Plex 250W PSUs and ran entire PC through a regular PSU (see pic), no change.

-         Borrowed a working GTX970 from Friend, setup with dual PSUs, still crashes.

-         Put GTX970 in PCI-e Slots directly, still crashes

-         GTX970 with regular PSU works (even with PCI-e Raiser cables)

 

So the only stable configuration that works is when both the PSUs and the GPU are replaced.

But all this at least eliminates the following error-sources:

-         Mainboard

-         CPU

-         RAM

-         SSD

-         Raiser-Cables

 

What really haunts me, is that initially in 2017 the computer worked in the same configuration before the frame was completed. (see table test pic)

I used furmark to stress the GPU and Prime95 to stress the CPU and proofed that it works under simultaneous load.

At that time I didn’t have the cooling rig, so I used 3 fans on a radiator. Those fans are not used now which results in less power usage.

 

This eliminates the following error-source:

-         Not enough power from the dual PSU setup.

The power draw graph of the GTX1080 suggests that power could be an issue. (pic 2) (eventhough already proven that it isn’t two years ago)
So I hooked up the regular power supply to the GPU alone and ran the PC through the other PSUs.

-         PC doesn’t crash, but GPU performs only 4fps in furmark.

 

You likely want to point out the special setup with the two micro PSU connected through the add2psu adapter.

But remember the PC still crashes when those are taken out of the equation entirely. And initially the setup worked flawlessly with those two PSUs two years ago.

A test done by eteknix.com with same Mobo, CPU and a GTX980Ti (same power draw) shows 368 Watts power draw under full combined load. (pic)

 

 

List of Hardware: (and which PSU it is hooked up to, see attached assembly diagram.)

-         PSU :                                2x HDplex 250 Hi-Fi DC-ATX   250W, max. peak is 300W                (www.hdplex.com)

-         PSU connector:               add2psu                                                     (http://www.add2psu.com/)

                                                   This connector does not share the power!!

-         Power :                            2x Dell PA-9E AC-Adapter 240W (recommended by HDplex)

 

Master PSU

-         Mainboard:                      AsRock Z170 Extreme7+ (LGA 1151, ATX)

-         CPU:                                 Intel Core i7 6700K Box (LGA 1151, 4Ghz, unlocked) 100W

-         Storage:                           Intel SSD

-         RAM:                                Hyper X Fury (2x 16GB, DDR4-2133, Dimm 288)

 

Slave PSU (201W total components, max. peak 296W)

-         GPU:                                EVGA GeForce GTX 1080 FE (8GB) (178W, max. peak 273W)

-         Pump:                              EKWB - EK-DBAY D5 PWM (23W)

 

 

 

 

 

 

 

PC assembly diagram

 

 

 

 

Original test setup with dual stresstest (both GPU / CPU) successful for 4 hours:

 

 

 

 

 

Stresstest at the time:

 

 

 

 

 

GTX1080 power consumption

 

 

 

 

When I used a regular PSU (didn't help)

 

 

 

Mainboard diagram

[Turtle Rig]

If you tried a different slot and still crahes.  Then try booting into safe mode and run DDU "Display Driver Uninstaller" and do a clean and restart ,, and back into normal mode and now install latest WHQL drivers but do custom install and don't install geforce experience as that has bugs.

[KzE]

sounds intreguing. We didn't install experience though.

[KzE]

I did the whole thing DDU (Display Driver Uninstaller) every time, and installed:

 

EVGA Driver:

- newest

- version that worked two years ago

- oldest version

 

nVidia Driver:

- newest

- version that worked two years ago

- oldest version

 

 

FPS / WATTS

In all versions the fps never went past 6 in the stresstest with the GTX 1080.

 

I tried my friend's GTX970 again and got 22fps out of it. It drew 278 Watts.

My GTX 1080 got 6 fps and drew 156 Watts.

I find this very interesting. As if it is somehow throttled.

 

For this whole setup I used a brand new never used 650W corsair PSU.

So there is no way my dual Mini-PSU has anything to do with it. (they were entirely disconnected)

 

 

HWmonitor received all sensor data with any driver version and the cards

was never too hot. The device manager showed all versions as installed without any problems.

 

 

 

What else can I do?

 

 

 

 

 

GTX970 results

 

 

 

 

 

GTX1080 results

 

 

[KzE]

So I tried my GTX 1080 in a friends PC and there it does 125fps.

This means the GPU runs good.

 

But the same card in my wall PC, with the ordinary corsair 650W PSU

only delivers 4fps. This indicates a problem not related to my dual 250W Mini-PSU setup... no?

 

Just doesn't make sense to me..