Question Asus Z490-E works with i7-11700K but not i5-10400F or i5-10500

[Satcomman]

I have recently upgraded my main machine and want to reuse some of the old parts to upgrade my daily driver.

The motherboard is an ASUS ROG Strix Z490-E Gaming. When I insert my i7-11700K the motherboard starts and allows me to access the BIOS.

When I insert either the 10400F or 10500 the system will not start. The fans and LEDs start momentarily and then stop. I get no fault LEDs and the Q-Code briefly flashes 00.

I have removed everything that is not needed and tried two different PSUs. There are no disks or SSDs attached. There are 2 16GB Corsair DDR4 DIMMs and a MSI GTX970 installed .

I have reset to factory defaults and when the i7-11700k was fitted I have updated the BIOS to the latest rev.

As previously stated when the i7-11700K is installed it works correctly.

What am I doing wrong? Any help will be much appreciated.

 

[Lutfij]

Welcome to the forums, newcomer!

According to the CPU's support list;

ROG STRIX Z490-E GAMING | Motherboards | ROG Global

The flagship ROG Strix Z490-E Gaming motherboard features boosted power delivery, optimized cooling, WiFi 6, and AI Overclocking, AI Cooling and AI Networking. This high-performance motherboard has cyberpunk-inspired aesthetics for a unique build.

rog.asus.com

you'll need at least BIOS version 0403 to be able to operate the 10th Gen i5's listed above. Conversely, you'll need BIOS version 2103 at the very least to be able to operate the 11th Gen i7's listed above.

I would inspect the CPU's socket for any bent or broken pins. Since I'm assuming you're using an aftermarket cooler, try and have the case to the side and rest the cooler on the IHS without mounting it and see if that helps.

For the sake of relevance, please state the BIOS version you're on at this moment of time.

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. Include all parts used to troubleshoot and the age of the PSU as you've stated using another one.

 

[Satcomman]

Welcome to the forums, newcomer!

According to the CPU's support list;

ROG STRIX Z490-E GAMING | Motherboards | ROG Global

The flagship ROG Strix Z490-E Gaming motherboard features boosted power delivery, optimized cooling, WiFi 6, and AI Overclocking, AI Cooling and AI Networking. This high-performance motherboard has cyberpunk-inspired aesthetics for a unique build.

rog.asus.com

you'll need at least BIOS version 0403 to be able to operate the 10th Gen i5's listed above. Conversely, you'll need BIOS version 2103 at the very least to be able to operate the 11th Gen i7's listed above.

I would inspect the CPU's socket for any bent or broken pins. Since I'm assuming you're using an aftermarket cooler, try and have the case to the side and rest the cooler on the IHS without mounting it and see if that helps.

For the sake of relevance, please state the BIOS version you're on at this moment of time.

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. Include all parts used to troubleshoot and the age of the PSU as you've stated using another one.

Many thanks for replying.
The BIOS rev is 3201 (latest from ASUS).
The CPU cooler is an Arctic Freezer 34 Esport
The motherboard is not in a chassis, it is on my desk.
The motherboard was in a chassis with the i7-11700K triple booting running Windows 11, Windows 11 Insider and Fedora Linux for over a year using a one year old Gigabyte PSU.

The motherboard was then connected to a Corsair CX550M PSU which is about three years old. This worked perfectly. The CPU was removed and replaced with an i5-10400F. This did not work.

The PSU was then changed for an EVGA 700BR, about three years old, but not used for two years due to having to have an adapter fitted to supply the CPU 4-pin socket. This still did not work.

The i7-11700K was reinserted and the system worked as expected.

The CPU was then changed for an i5-10500, this did not work.

The 10400F and 10500 were tested in my other system on a Z590 motherboard. They worked as expected.

Due to the fact that the 11700K has a TDP of 125W and both the others have a TDP of 65W (ie about half) it is very unlikely to be the PSU. The 11700K works with all PSUs, the other two work with none.

I have inspected the CPU socket on several occasions using an inspection lamp and a high powered magnifying lens, there are no bent and/or missing pins. If there were some damaged pins the 11700K would definitely not work as it uses more pins (more PCI-e lanes)

I wonder if it is related to the fact that the 11700K is 11th gen and the other two are 10th gen. I think that it is unlikely to be that because the motherboard was designed for 10th gen and only worked with 11th gen after a BIOS update.

I have spent the last two weeks trying to work out what the problem is and have had to finally ask for help.

Once again, thanks for your time.