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Cannot boot anymore, restarts at code B4

MithrandirX
Level 7
Hello,

I'm at work, so I'm missing a few pieces of info in my template that I'll update later today.


Motherboard model: Asus Rampage V Extreme

UEFI Version: BIOS 3301.

CPU: Intel Core i7-5930K (not overclocked)

Memory kit part number (s) and amount in GB: Corsair Vengeance LPX Series Low Profile 32 GB (4x 8 GB) DDR4 2666 MHz CL16

GPU: 2 x Gigabyte GV-N970G1 GAMING-4GD - GeForce GTX 970 4 GB (SLI)

SSD/HDDs/Optical drives: Samsung SSD 850 PRO 256 Go + 3 Western Digital Green 2GB HDD(have to confirm the 3 WD) + ASUS BW-16D1HT (Blu-ray writer)

Sound Card : ASUS Xonar DX

PSU: Corsair AX1200i 80PLUS Platinum

USB Devices (model/version number): Logitech G910 mechanical keyboard + Madcatz R.A.T MMO mouse

Monitor: BenQ 32" LED - BL3201PT


CPU Cooler: Enermax ETS-T40-TB

PC CASE: Phanteks Enthoo Primo

Operating system: Windows 10 (Activated)


Drivers Installed (include version): Have to check but I don't think that's relevant here

Any third Party temp/voltage software installed: No

System Overclocked (provide details)?


Issue :

I didn't have a lot of time to investigate the issue yet, so there are still things I have to try (swap components mostly) but since this issue seems quite peculiar, I'm wondering if anyone might know anything about already.

My PC is most of the time turned on, but a few days ago, I wanted to put it in sleep mode because of the warm weather we had this week-end (the room the PC is in was getting a bit too warm).

The issue then was that each time I put it in sleep mode, it was turning back on after a few seconds.
I didn't pay much attention to the issue at the time, and decided to shut it down instead.
It shut down correctly without any strange issues, but when I tried turning it back on the next day, it wouldn't boot anymore.
The first strange thing was that the power button on the tower wasn't doing anything.

I then decided to use the start button on the motherboard itself and it turned on.
It goes through quite a few codes, but after 9C, 99 and B4, it just turns off and starts again (I have to turn off the power supply to stop the cycle).
Nothing is ever displayed on the screen.

Since the B4 code seems to be related to USB hot plug, I tried disconnecting everyhing connected in USB (including the internal USB that connects to the tower's front USB's), but it didn't change a thing.

I also tried booting in safe mode with the button on the motherboard, but the result is the same.

I thought it could be related to the power button of my tower because of the strange behavior I had when trying to put the computer to sleep mode first, then whenI couldn't turn it on with the tower's power button, so I tried unplugging the tower's power and reset cables (as well as the LEDs and other ones) from the motherboard, but the issue remains.

Does anyone know what could be the problem?

If not, as soon as I have time, I'll try removing ram (leaving only one, then another), removing one graphic card at a time, trying the PSU from another computer, etc..
Is there something specific I should try too?

Thanks in advance !

Best regards,
Sébastien
12,508 Views
6 REPLIES 6

Arne_Saknussemm
Level 40

Arne Saknussemm wrote:
Have you tried clearing CMOS?


I haven't tried that yet, as I thought the "Safe boot" button (which I tried) was using the default BIOS options (so the same thing as Clear CMOS).

If it is indeed different, I will try that tonight, thanks.

I guess I should also try updating to the latest version of the BIOS with the USB BIOS Flashback (since I can't access the BIOS).

I've tried clearing the CMOS, the problem remains but the system now shuts down and restarts at B2 instead of B4.

Arne_Saknussemm
Level 40
B2 is VGA initialization

I would try switching to your second BIOS....clear cmos and try again and/or update BIOS 1 to latest BIOS....BIOS flashback method.

Maybe reseat GPU....power cables etc...if you have a spare PSU try that....

Arne Saknussemm wrote:
B2 is VGA initialization

I would try switching to your second BIOS....clear cmos and try again and/or update BIOS 1 to latest BIOS....BIOS flashback method.

Maybe reseat GPU....power cables etc...if you have a spare PSU try that....


Thank you, I'll try those things and report the result.

I've tried all those things, except replacing the PSU (which I can't right now).

The computer is still restarting after the same amount of time, with different last Qcodes after flashing the latest BIOS, or when removing the GPU's.

I think the QCode is not really telling much in this case, it seems to be whatever the code is after that set amount of time (which seems to be the same each time)