Asus X670e not powering on - understood better 95% fixed

ginjaninja · 28 Feb 2026 at 15:32

Well thats 48 hours troubleshooting i wont get back. Im too old for this ..just want things to work.
Had to strip down PC and tinker for 2 days, hope this saves someone grief and wondering if anyone has seen similar before?

Topics: Asus Flashback, Asus Bios corruption, ERP Bios Setting

My Setup
Asus x670e Tuf Gaming Plus
7800x3d
Corsair 2x32GB CL30
Be Quiet Dark Power 13

After months of normal operation, The PC wouldn't boot one morning.
Stripped everything down, could occasionally get Motherboard to start without understanding why but wouldn't get past Memory training (permanent orange light).
Turned out the bios flashback Led was automatically coming on. <- this could be some sort of Asus failsafe after failed power up attempts? PC would never start if Flashback process had auto started.
Tried to complete 'bios flashback' for real, would never fail or complete, LED just flashed forever.
Tested Pin 4/5 paperclip on PSU to confirm the PSU started ok.
I eventually got flashback to complete, the last thing i tried was to use Rufus rather than Windows 10 to create a MBR Partition on USB stick...i think this is what made it work... cant be sure.
I could now occasionally get the board to start up and after flashback the computer would now pass memory training, occasionally the mboard still went into flashback mode on powerup. Having failed power up attempts seemed to increase likelihood of flashback auto starting.

Once the PC had started successfully i could use it and restart PC as many times as i liked..but if i shut PC down then it was pot luck if the board would power on again. Leaving off for 10 minutes seemed to increase chances.

I read someone had similar symptoms and enabled ERP and disabled fast boot in bios and OS (although on recent Asus bios boots are much faster in any case, maybe MCR is on by default now?). I think ERP is a workaround for me to achieve reliable power on. Now when i shutdown, there is a relay click on the PSU which wasn't there before and the RGBs lights on the motherboard go out completely. In this state the PC reliably powers on and I've had no issues since.

Conclusion:
possibly Mboard (less likely PSU) is broken
Enabling ERP was a workaround but why?
Not having power on failures means the board doesn't autostart flashback (further hampering power on attempts)

So it seems the Asus motherboard was thinking for itself, had got into a state where it thought the bios was corrupted, was auto starting flashback when not asked for. Have started an Asus ticket and will request an RMA. Anyone had similar experience? i wonder whether the motherboard is rightly or wrongly not passing some failsafe and that makes it decide not to power on, I wonder whether it is possible to query a motherboard to get a log of the reasons it didn't power on previously.

Have ordered a An Asrock x870e + 9800x3d in case have to RMA board and to aid further troubleshooting.

Tetras · 28 Feb 2026 at 15:49

ginjaninja said:
I read someone had similar symptoms and enabled ERP and disabled fast boot in bios and OS (although on recent Asus bios boots are much faster in any case, maybe MCR is on by default now?). I think ERP is a workaround for me to achieve reliable power on. Now when i shutdown, there is a relay click on the PSU which wasn't there before and the RGBs lights on the motherboard go out completely. In this state the PC reliably powers on and I've had no issues since.

That sounds more like some kind of fast boot/suspend bug? With fast boot enabled I don't think the PC actually shuts down properly, which could explain the relay click only occuring now.

ginjaninja said:
Not having power on failures means the board doesn't autostart flashback (further hampering power on attempts)

Is the USB port that is tied to USB flashback in use/occupied?

jigger · 28 Feb 2026 at 16:19

Asus need stop this BIOS update from windows nonsense. Windows is dodgy enough as it is.

ginjaninja · 28 Feb 2026 at 16:33

Tetras said:
That sounds more like some kind of fast boot/suspend bug? With fast boot enabled I don't think the PC actually shuts down properly, which could explain the relay click only occuring now.

Is the USB port that is tied to USB flashback in use/occupied?

The Relay click didnt start until after i enabled ERP in Bios, Fast boot was already disabled in Bios and OS prior.

No the USB port for flashback is not populated. The motherboard just decides to start flashback.

ginjaninja · 6 Mar 2026 at 11:48

Late to party probably on this one but amazingly Asus dont support their own warranties now, "Have to raise with seller".Asus were not interested in troubleshooting the issue, pretty poor support IMO. The seller is saying the board isnt available anymore so would only offer a % of the purchase price due to age, need to check legalities/my rights on this that sounds rubbish given i had to pay full price (in todays money) for a replacement. I expect a motherboard to outlive its usefullness if it doesnt break in the warranty period, motherboards shouldnt just die after a couple of years of working unless poor components are being used.

jigger · 6 Mar 2026 at 11:57

ginjaninja said:
Late to party probably on this one but amazingly Asus dont support their own warranties now, "Have to raise with seller".Asus were not interested in troubleshooting the issue, pretty poor support IMO. The seller is saying the board isnt available anymore so would only offer a % of the purchase price due to age, need to check legalities/my rights on this that sounds rubbish given i had to pay full price (in todays money) for a replacement. I expect a motherboard to outlive its usefullness if it doesnt break in the warranty period, motherboards shouldnt just die after a couple of years of working unless poor components are being used.

Lovely, especially considering it’s an Asus feature that most likely the caused the failure.

Vimes · 17 Mar 2026 at 08:26

ginjaninja said:
Late to party probably on this one but amazingly Asus dont support their own warranties now, "Have to raise with seller".Asus were not interested in troubleshooting the issue, pretty poor support IMO. The seller is saying the board isnt available anymore so would only offer a % of the purchase price due to age, need to check legalities/my rights on this that sounds rubbish given i had to pay full price (in todays money) for a replacement. I expect a motherboard to outlive its usefullness if it doesnt break in the warranty period, motherboards shouldnt just die after a couple of years of working unless poor components are being used.

That was similar to the reply that I got also from Asus when dealing with a Asus router failure. The router failed after 35 months, just within the 3 years warranty. The retailer did not want to know at that point, and Asus continually pushed me to the retailer. It took a massive amount of effort, eventually the retailer refunded me, just as Asus were making positive attempts to become involved, with making a compensation offer.
It is not unreasonable, the box of the router still had the 3 years warranty sticker and the retailer advertised still, as such, to expect a form of cooperation, and communication between the manufacturer and retailer. When dealing with extended type warranties, Potentially it leaves the customer in the middle with little meaningful support.

It was not bought from OCUK.