RTX 3090 not detected with i9 but detected with i7

[chatJPT]

I have a very peculiar issue. My MSI RTX 3090 Gaming X Trio 24 GB is not being detected by the motherboard while running my i9 9900k but when I swap it for an i7 8700k, the GPU is detected and works just fine.  Here full specs of system:

CPU: i9 9900k 

Motherboard:  TUF z390-PLUS Gaming Wi-fi (bios driver 3006 (most recent, 2021))

also tried: ROG STRIX Z390-E Gaming (up to date drivers)

also tried: Asustek prime B360M-A

Ram: Corsair 4x 16gb 3200mhz RGB pro(tried with 1, 2 and 4 sticks in, as well as one stick of hyperX 8gb) 

m2 nvme: Intel SSDPEKNW02 2TB  in slot between gpu and cpu. 

Cooler: Corsair H115i Cappellix XT

PSU: EVGA Supernova 1600W

GPU: MSI RTX 3090 Gamin X Trio 24 GB (PCIe 1 x16 slot) but also tried slot 2 on both motherboards with no detection.

Running Windows 11 but also tried on Windows 10

Troubleshooting tried:
-CMOS reset

-Windows updated drivers of all kind (in win 10 and win 11)

- Tried uninstalling intel graphics device in device manager

- Tried various Bios settings :

               - Forcing Gen 3 
               - Forcing PEG as primary display

               - Rebar on and off

               - Ram stock, XMP1, XMP2

               - Disabled fast boot

               - Pretty much every other bios tweak in the first 2 pages of various google searches. 

Hypothesis:

-hidden issue with the i9 PCIe controller (if that's a thing, only chatGPT seems to have come up with this possibility so I'm dubious)

-Motherboard related power delivery issue on boot(but 3dMark has many scores registered with the same cpu, gpu, motherboard combo)

-Mysterious disturbance in the Force, Cosmic misalignement, God does not love me. 

Any help in diagnosing or troubleshooting this issue would be much appreciated!

[Steven_Intel]

Hello chatJPT,

Thank you for posting on the Intel® communities.

Based on the steps you have performed already, I will need to do further research about this. As soon as I have an update, I will let you know.

Best regards,

Steven G.

Intel Customer Support Technician.

[Vlares · Accepted solution]

If your video card is not detected on different motherboards with this processor, then the problem is in the PCI bus 100% on the processor or video card. Most likely, the first pairs of PCI bus are damaged. Check the surface of the processor, maybe there is dirt on the contact. Check how the video card is detected on that other processor i7 8700k, whether the full PCI Express x16 works or only x8, x4. If the video card is detected only as 8x or 4x, then the line in the middle of the PCI bus of VGA is damaged.

I had a case when not all video cards were detected on the Intel platform and there was a problem in the damaged PCI bus of the processor itself. The problem was fixed only after 1-2 years, when the processor died completely and I replaced it under warranty, and then there were no problems with video cards.

The PСI bus is damaged most often by static from the user, 95+% of the cases. There are also cases of increased voltage in the system when the monitor and the computer do not have a common ground.

[chatJPT]

Thanks for the insight, after all the google searches and testing and troubleshooting, I capitulated and decided to ask... yup you guessed it: ChatGPT, well it told me: "This is a long shot but it is possible that your issue is caused by a damaged PCI bus in your processor. Unfortunately I cannot provide any tests that could prove this to be the case but given all the steps you have taken thus far, you should contact intel and inquire about your warranty." Then I came here, as a last ditch effort to get an answer from Intel, Intel was useless, as expected but Vlares confirmed what the machine said about the broken machine which was more accurate than the people who made the now broken machine which is ironic. Now I bought this cpu in 2019, so probably no warranty, a real bummer to have to downgrade my cpu as I upgrade my GPU but at least for now it runs all my games on Ultra and I have learned a lot about computers so I'll focus on that. 

Thank you Vlares for taking the time to respond!

Best,

[Steven_Intel]

Hello chatJPT,

Many thanks for your patience on this matter.

Based on the information provided, it is recommended to ensure GPU compatibility with the board(s) manufacturer, since when looking at the CPU specifications, they have the same characteristics and should be supported.

Best regards,

Steven G.

Intel Customer Support Technician.

[Vlares]

So he tested on 3 different motherboards, it is already obvious that the problem is not in the motherboard. Once upon a time there was such a BIOS bug, to my mind on 61 chipsets, that some video cards did not start there, but that was a very long time ago. And here are 3 different motherboards.

[Jean_Intel]

Hello everyone,

We appreciate the information provided.

We will do further research on this matter and post the response on this thread once available.

Best regards,

Jean O. 

Intel Customer Support Technician

[Steven_Intel]

Hello chatJPT,

Based on the information and steps performed, my recommendation is to proceed with the RMA process for your Intel® Core™ i9-9900K Processor.

After verifying that your warranty is still active (here: https://supporttickets.intel.com/warrantyinfo?lang=en-US), directly contact Intel Customer Support to initiate the RMA process (you cannot do this through the forums). 

Here are pages where you can look up contact information, including local/country phone numbers, by geography: 

U.S. and Canada: Intel Customer Support https://www.intel.com/content/www/us/en/support/contact-support.html 

Europe, Middle East and Africa: Intel Customer Support EMEA https://www.intel.com/content/www/us/en/support/contact-support/emea-contact.html 

Asia-Pacific: Intel Customer Support APAC https://www.intel.com/content/www/us/en/support/contact-support/apac-contact.html 

Latin America: Intel Customer Support LAR https://www.intel.com/content/www/us/en/support/contact-support/lar-contact.html 

Chat support: http://intelsupportchat.force.com/icslivechat/ics_tech_processor_ww_english_Chat

Please keep in mind that this thread will no longer be monitored by Intel. 

Thank you for your understanding.  

Best regards,

Steven G.

Intel Customer Support Technician.