Stuck in boot loop if NO PCIe GPU is installed

[GoGoWe]

Hello Linus Community, 

 

I have a very weird and for me unexplainable problem.

A colleague of my built an office pc and could not install windows on to it. The system started to boot from the USB, crashed short before showing the installing screen and rebooted.
Yesterday I tried many different things. After plugging an old AMD GPU in the PCIe slot, connecting it with the PSU and with a display via HDMI, I achieved to install Windows. Everything worked after installing Windows and all important drivers and updates, even if I plug the HDMI cable in the motherboard and booted with the internal GPU/onboard GPU.

 

And now the "funny" thing. 
When I remove the GPU or unplug the power cable of the PSU from it (so it gets to juice) the machine crashes shortly before finished booting into Windows.

Can someone please explain me this? I built hundreds of systems and never had a similar error. The only thing I suppose to and didn't try is to change the PSU (630W Thermaltake Berlin) because I had no at hand.

 

Specs:

• MoBo ASRock H310M-HDV
• CBU Intel Core i3 8100
• SSD Samsung EVO 860 SSD 500GB
• RAM 8 GB DDR4 
• PSU 630W Thermaltake Berlin
• Windows 10 Home*

 

*(EDIT)

[Varusal]

Did you tried to boot into the Windows Safe Mode? Could be an driver issue.

[NelizMastr]

First of all, that PSU is pretty bad, but that's not really the main issue, I think.

 

Which Windows version did you install? Windows 7 and 8.x aren't supported on Coffee Lake. If that's not the case, then it's time for further testing.

 

- Run Memtest86+ for a good few hours to verify the memory is stable

- If that checks out then the problem is either the board or the CPU. I get the feeling that the iGPU might be defective. Rare, but not unheard of.

[userzero]

Pull the CMOS battery for a short while, let it clear, put it back in and try to get into the BIOS and look at the GPU preference. I think the option to use PCI only or similar for the graphics is there. You can tell it to only use PCI-E or whatever on some systems so it could be that.

[GoGoWe]

13 minutes ago, SirMorokei said:

Did you tried to boot into the Windows Safe Mode? Could be an driver issue.

No, I didn't but I don't think it will help. How a told, even the Windows Installer from a USB didn't want to start.
 

13 minutes ago, NelizMastr said:

First of all, that PSU is pretty bad, but that's not really the main issue, I think.

 

Which Windows version did you install? Windows 7 and 8.x aren't supported on Coffee Lake. If that's not the case, then it's time for further testing.

 

- Run Memtest86+ for a good few hours to verify the memory is stable

- If that checks out then the problem is either the board or the CPU. I get the feeling that the iGPU might be defective. Rare, but not unheard of.

1

Yes I know I think it should be a cheap office pc. 
I use Windows 10. 

I will check Memtest86. First I also thought it could be a broken iGPU but it works when a PCIe GPU is plugged in. Even some Benchmarks and Games work.
 

16 minutes ago, userzero said:

Pull the CMOS battery for a short while, let it clear, put it back in and try to get into the BIOS and look at the GPU preference. I think the option to use PCI only or similar for the graphics is there. You can tell it to only use PCI-E or whatever on some systems so it could be that.

 

I can get into the BIOS only if Windows 10 starts booting it crash. I changed to iGPU and it works until I unplug the PCIe GPU.
 

[userzero]

That's not what I'm saying. I'm saying to look for the GPU/Graphics preference setting if it exists on that BIOS. You will be able to choose auto/onboard/PCI only etc..

 

If Windows booting is causing it to crash, then unplug the hard drive and do it.

[GoGoWe]

I know, I have the option and I changed it to onboard.

[GoGoWe]

On 3.9.2018 at 11:16 AM, NelizMastr said:

First of all, that PSU is pretty bad, but that's not really the main issue, I think.

 

Which Windows version did you install? Windows 7 and 8.x aren't supported on Coffee Lake. If that's not the case, then it's time for further testing.

 

- Run Memtest86+ for a good few hours to verify the memory is stable

- If that checks out then the problem is either the board or the CPU. I get the feeling that the iGPU might be defective. Rare, but not unheard of.

Sorry for the late answer.
Today I tested some more things.

1. Memtest86 made 5 passes and 0 errors
2. Cinebench running with iGPU without any problems
3. Prime95 on Small FFTs preset is running over half an hour without any crashes

But the whole system still crashes immediately after trying to boot and restart, if i have no GPU plugged into the PCI slot (and connected to the PSU).
Here some verification screenshots.
The iGPU is working and both GPUs are detected.

EDIT: Changed the GPU from the AMD Readon to a GTX 750 ti (without extra Power Cable) and the system booted normaly. I even don't use any driver for the GTX. I really have no clue, why it crashes without GPU. The only thing that seems meaningful is a defekt iGPU.

Edited September 23, 2018 by GoGoWe
additional information

[DanCaveman]

On 9/23/2018 at 4:08 AM, GoGoWe said:

Sorry for the late answer.
Today I tested some more things.

1. Memtest86 made 5 passes and 0 errors
2. Cinebench running with iGPU without any problems
3. Prime95 on Small FFTs preset is running over half an hour without any crashes

But the whole system still crashes immediately after trying to boot and restart, if i have no GPU plugged into the PCI slot (and connected to the PSU).
Here some verification screenshots.
The iGPU is working and both GPUs are detected.

EDIT: Changed the GPU from the AMD Readon to a GTX 750 ti (without extra Power Cable) and the system booted normaly. I even don't use any driver for the GTX. I really have no clue, why it crashes without GPU. The only thing that seems meaningful is a defekt iGPU.

Did you ever figure out what the issue was?

I am having the exact same issue.  I bought some used components and was starting to think there was an issue; however, when I put a PCIe GPU in, everything works great.  If I remove it, the computer loads to the login screen before rebooting.

I don't plan to use it without a gpu, but just wondering if there is some other hidden issue with the CPU/Motherboard.  I have an i9-9900k and gigabyte aorus z390 pro wifi board.

At this point, I plan to ignore the issue, but it is going to stick in my brain unless I find a solution.

Edited June 30, 2022 by DanCaveman
asking the question.